Gastrointestinal Cancer

In the setting of conflicting national screening guidelines, the incidence of distant- and regional-stage colorectal adenocarcinoma (CRC) has been increasing in individuals aged 46-49 years, a cross-sectional study of stage-stratified CRC found.

It is well known that CRC is becoming more prevalent generally in the under 50-year population, but stage-related analyses have not been done.

Staging analysis in this age group is important, however, as an increasing burden of advance-staged disease would provide further evidence for earlier screening initiation, wrote Eric M. Montminy, MD, a gastroenterologist at John H. Stroger Hospital of County Cook, Chicago, Illinois, and colleagues in JAMA Network Open.

Montminy_Eric_IL_web.jpg

• Distant adenocarcinoma IRs increased faster than other stages: annual percentage change (APC), 2.2 (95% CI, 1.8-2.6).
• Regional IRs also significantly increased: APC, 1.3 (95% CI, 0.8-1.7).
• Absolute regional IRs of CRC in the age bracket of 46-49 years are similar to total pancreatic cancer IRs in all ages and all stages combined (13.2 of 100,000) over similar years. When distant IRs for CRC are included with regional IRs, those for IRs for CRC are double those for pancreatic cancer of all stages combined.
• The only decrease was seen in localized IRs: APC, -0.6 (95% CI, -1 to -0.2).

“My best advice for clinicians is to provide the facts from the data to patients so they can make an informed health decision,” Dr. Montminy said. “This includes taking an appropriate personal and family history and having the patient factor this aspect into their decision on when and how they want to perform colon cancer screening.”

His institution adheres to the USPSTF recommendation of initiation of CRC screening at age 45 years.
 

Findings From 2000 to 2020

During 2000-2020 period, 26,887 CRCs were diagnosed in adults aged 46-49 years (54.5% in men).

As of 2020, the localized adenocarcinoma IR decreased to 7.7 of 100,000, but regional adenocarcinoma IR increased to 13.4 of 100,000 and distant adenocarcinoma IR increased to 9.0 of 100,000.

Regional adenocarcinoma IR remained the highest of all stages in 2000-2020. From 2014 to 2020, distant IRs became similar to localized IRs, except in 2017 when distant IRs were significantly higher than localized.
 

Why the CRC Uptick?

“It remains an enigma at this time as to why we’re seeing this shift,” Dr. Montminy said, noting that etiologies from the colonic microbiome to cellphones have been postulated. “To date, no theory has substantially provided causality. But whatever the source is, it is affecting Western countries in unison with data demonstrating a birth cohort effect as well,” he added. “We additionally know, based on the current epidemiologic data, that current screening practices are failing, and a unified discussion must occur in order to prevent young patients from developing advanced colon cancer.”

Meyer_Joshua_PA_web.jpg

Offering his perspective on the findings, Joshua Meyer, MD, vice chair of translational research in the Department of Radiation Oncology at Fox Chase Cancer Center in Philadelphia, said the findings reinforce the practice of offering screening to average-risk individuals starting at age 45 years, the threshold at his institution. “There are previously published data demonstrating an increase in advanced stage at the time of screening initiation, and these data support that,” said Dr. Meyer, who was not involved in the present analysis.

More research needs to be done, he continued, not just on optimal age but also on the effect of multiple other factors impacting risk. “These may include family history and genetic risk as well as the role of blood- and stool-based screening assays in an integrated strategy to screen for colorectal cancer.”

There are multiple screening tests, and while colonoscopy, the gold standard, is very safe, it is not completely without risks, Dr. Meyer added. “And the question of the appropriate allocation of limited societal resources continues to be discussed on a broader level and largely explains the difference between the two guidelines.”

This study received no specific funding. Co-author Jordan J. Karlitz, MD, reported personal fees from GRAIL (senior medical director) and an equity position from Gastro Girl/GI On Demand outside f the submitted work. Dr. Meyer disclosed no conflicts of interest relevant to his comments.

In the setting of conflicting national screening guidelines, the incidence of distant- and regional-stage colorectal adenocarcinoma (CRC) has been increasing in individuals aged 46-49 years, a cross-sectional study of stage-stratified CRC found.

It is well known that CRC is becoming more prevalent generally in the under 50-year population, but stage-related analyses have not been done.

Staging analysis in this age group is important, however, as an increasing burden of advance-staged disease would provide further evidence for earlier screening initiation, wrote Eric M. Montminy, MD, a gastroenterologist at John H. Stroger Hospital of County Cook, Chicago, Illinois, and colleagues in JAMA Network Open.

Montminy_Eric_IL_web.jpg

• Distant adenocarcinoma IRs increased faster than other stages: annual percentage change (APC), 2.2 (95% CI, 1.8-2.6).
• Regional IRs also significantly increased: APC, 1.3 (95% CI, 0.8-1.7).
• Absolute regional IRs of CRC in the age bracket of 46-49 years are similar to total pancreatic cancer IRs in all ages and all stages combined (13.2 of 100,000) over similar years. When distant IRs for CRC are included with regional IRs, those for IRs for CRC are double those for pancreatic cancer of all stages combined.
• The only decrease was seen in localized IRs: APC, -0.6 (95% CI, -1 to -0.2).

“My best advice for clinicians is to provide the facts from the data to patients so they can make an informed health decision,” Dr. Montminy said. “This includes taking an appropriate personal and family history and having the patient factor this aspect into their decision on when and how they want to perform colon cancer screening.”

His institution adheres to the USPSTF recommendation of initiation of CRC screening at age 45 years.
 

Findings From 2000 to 2020

During 2000-2020 period, 26,887 CRCs were diagnosed in adults aged 46-49 years (54.5% in men).

As of 2020, the localized adenocarcinoma IR decreased to 7.7 of 100,000, but regional adenocarcinoma IR increased to 13.4 of 100,000 and distant adenocarcinoma IR increased to 9.0 of 100,000.

Regional adenocarcinoma IR remained the highest of all stages in 2000-2020. From 2014 to 2020, distant IRs became similar to localized IRs, except in 2017 when distant IRs were significantly higher than localized.
 

Why the CRC Uptick?

“It remains an enigma at this time as to why we’re seeing this shift,” Dr. Montminy said, noting that etiologies from the colonic microbiome to cellphones have been postulated. “To date, no theory has substantially provided causality. But whatever the source is, it is affecting Western countries in unison with data demonstrating a birth cohort effect as well,” he added. “We additionally know, based on the current epidemiologic data, that current screening practices are failing, and a unified discussion must occur in order to prevent young patients from developing advanced colon cancer.”

Meyer_Joshua_PA_web.jpg

Offering his perspective on the findings, Joshua Meyer, MD, vice chair of translational research in the Department of Radiation Oncology at Fox Chase Cancer Center in Philadelphia, said the findings reinforce the practice of offering screening to average-risk individuals starting at age 45 years, the threshold at his institution. “There are previously published data demonstrating an increase in advanced stage at the time of screening initiation, and these data support that,” said Dr. Meyer, who was not involved in the present analysis.

More research needs to be done, he continued, not just on optimal age but also on the effect of multiple other factors impacting risk. “These may include family history and genetic risk as well as the role of blood- and stool-based screening assays in an integrated strategy to screen for colorectal cancer.”

There are multiple screening tests, and while colonoscopy, the gold standard, is very safe, it is not completely without risks, Dr. Meyer added. “And the question of the appropriate allocation of limited societal resources continues to be discussed on a broader level and largely explains the difference between the two guidelines.”

This study received no specific funding. Co-author Jordan J. Karlitz, MD, reported personal fees from GRAIL (senior medical director) and an equity position from Gastro Girl/GI On Demand outside f the submitted work. Dr. Meyer disclosed no conflicts of interest relevant to his comments.

In the setting of conflicting national screening guidelines, the incidence of distant- and regional-stage colorectal adenocarcinoma (CRC) has been increasing in individuals aged 46-49 years, a cross-sectional study of stage-stratified CRC found.

It is well known that CRC is becoming more prevalent generally in the under 50-year population, but stage-related analyses have not been done.

Staging analysis in this age group is important, however, as an increasing burden of advance-staged disease would provide further evidence for earlier screening initiation, wrote Eric M. Montminy, MD, a gastroenterologist at John H. Stroger Hospital of County Cook, Chicago, Illinois, and colleagues in JAMA Network Open.

Montminy_Eric_IL_web.jpg

• Distant adenocarcinoma IRs increased faster than other stages: annual percentage change (APC), 2.2 (95% CI, 1.8-2.6).
• Regional IRs also significantly increased: APC, 1.3 (95% CI, 0.8-1.7).
• Absolute regional IRs of CRC in the age bracket of 46-49 years are similar to total pancreatic cancer IRs in all ages and all stages combined (13.2 of 100,000) over similar years. When distant IRs for CRC are included with regional IRs, those for IRs for CRC are double those for pancreatic cancer of all stages combined.
• The only decrease was seen in localized IRs: APC, -0.6 (95% CI, -1 to -0.2).

“My best advice for clinicians is to provide the facts from the data to patients so they can make an informed health decision,” Dr. Montminy said. “This includes taking an appropriate personal and family history and having the patient factor this aspect into their decision on when and how they want to perform colon cancer screening.”

His institution adheres to the USPSTF recommendation of initiation of CRC screening at age 45 years.
 

Findings From 2000 to 2020

During 2000-2020 period, 26,887 CRCs were diagnosed in adults aged 46-49 years (54.5% in men).

As of 2020, the localized adenocarcinoma IR decreased to 7.7 of 100,000, but regional adenocarcinoma IR increased to 13.4 of 100,000 and distant adenocarcinoma IR increased to 9.0 of 100,000.

Regional adenocarcinoma IR remained the highest of all stages in 2000-2020. From 2014 to 2020, distant IRs became similar to localized IRs, except in 2017 when distant IRs were significantly higher than localized.
 

Why the CRC Uptick?

“It remains an enigma at this time as to why we’re seeing this shift,” Dr. Montminy said, noting that etiologies from the colonic microbiome to cellphones have been postulated. “To date, no theory has substantially provided causality. But whatever the source is, it is affecting Western countries in unison with data demonstrating a birth cohort effect as well,” he added. “We additionally know, based on the current epidemiologic data, that current screening practices are failing, and a unified discussion must occur in order to prevent young patients from developing advanced colon cancer.”

Meyer_Joshua_PA_web.jpg

Offering his perspective on the findings, Joshua Meyer, MD, vice chair of translational research in the Department of Radiation Oncology at Fox Chase Cancer Center in Philadelphia, said the findings reinforce the practice of offering screening to average-risk individuals starting at age 45 years, the threshold at his institution. “There are previously published data demonstrating an increase in advanced stage at the time of screening initiation, and these data support that,” said Dr. Meyer, who was not involved in the present analysis.

More research needs to be done, he continued, not just on optimal age but also on the effect of multiple other factors impacting risk. “These may include family history and genetic risk as well as the role of blood- and stool-based screening assays in an integrated strategy to screen for colorectal cancer.”

There are multiple screening tests, and while colonoscopy, the gold standard, is very safe, it is not completely without risks, Dr. Meyer added. “And the question of the appropriate allocation of limited societal resources continues to be discussed on a broader level and largely explains the difference between the two guidelines.”

This study received no specific funding. Co-author Jordan J. Karlitz, MD, reported personal fees from GRAIL (senior medical director) and an equity position from Gastro Girl/GI On Demand outside f the submitted work. Dr. Meyer disclosed no conflicts of interest relevant to his comments.

TOPLINE:

A recent survey-based study found that only 4% of cancer survivors reported adhering to all four American Cancer Society (ACS) nutrition and physical activity guidelines, which include maintaining a healthy weight and diet, avoiding alcohol, and exercising regularly.

METHODOLOGY:

• The ACS has published nutrition and exercise guidelines for cancer survivors, which include recommendations to maintain a healthy weight and diet, cut out alcohol, and participate in regular physical activities. Engaging in these behaviors is associated with longer survival among cancer survivors, but whether survivors follow these nutrition and activity recommendations has not been systematically tracked.
• Researchers evaluated data on 10,020 individuals (mean age, 64.2 years) who had completed cancer treatment. Data came from the Behavioral Risk Factor Surveillance System telephone-based survey administered in 2017, 2019, and 2021, which represents 2.7 million cancer survivors.
• The researchers estimated survivors’ adherence to guidelines across four domains: Weight, physical activity, fruit and vegetable consumption, and alcohol intake. Factors associated with adherence were also evaluated.
• Overall, 9,121 survivors (91%) completed questionnaires for all four domains.

TAKEAWAY:

Only 4% of patients (365 of 9121) followed ACS guidelines in all four categories.

When assessing adherence to each category, the researchers found that 72% of cancer survivors reported engaging in recommended levels of physical activity, 68% maintained a nonobese weight, 50% said they did not consume alcohol, and 12% said they consumed recommended quantities of fruits and vegetables.

Compared with people in the general population, cancer survivors generally engaged in fewer healthy behaviors than those who had never been diagnosed with cancer.

The authors identified certain factors associated with greater guideline adherence, including female sex, older age, Black (vs White) race, and higher education level (college graduate).

IN PRACTICE:

This study highlights a potential “gap between published guidelines regarding behavioral modifications for cancer survivors and uptake of these behaviors,” the authors wrote, adding that “it is essential for oncologists and general internists to improve widespread and systematic counseling on these guidelines to improve uptake of healthy behaviors in this vulnerable patient population.”

SOURCE:

This work, led by Carter Baughman, MD, from the Division of Internal Medicine at Beth Israel Deaconess Medical Center, Boston, Massachusetts, was published online in JAMA Oncology.

LIMITATIONS:

The authors reported several study limitations, most notably that self-reported data may introduce biases.

DISCLOSURES:

The study funding source was not reported. One author received grants from the US Highbush Blueberry Council outside the submitted work. No other disclosures were reported.

A version of this article appeared on Medscape.com.

TOPLINE:

A recent survey-based study found that only 4% of cancer survivors reported adhering to all four American Cancer Society (ACS) nutrition and physical activity guidelines, which include maintaining a healthy weight and diet, avoiding alcohol, and exercising regularly.

METHODOLOGY:

• The ACS has published nutrition and exercise guidelines for cancer survivors, which include recommendations to maintain a healthy weight and diet, cut out alcohol, and participate in regular physical activities. Engaging in these behaviors is associated with longer survival among cancer survivors, but whether survivors follow these nutrition and activity recommendations has not been systematically tracked.
• Researchers evaluated data on 10,020 individuals (mean age, 64.2 years) who had completed cancer treatment. Data came from the Behavioral Risk Factor Surveillance System telephone-based survey administered in 2017, 2019, and 2021, which represents 2.7 million cancer survivors.
• The researchers estimated survivors’ adherence to guidelines across four domains: Weight, physical activity, fruit and vegetable consumption, and alcohol intake. Factors associated with adherence were also evaluated.
• Overall, 9,121 survivors (91%) completed questionnaires for all four domains.

TAKEAWAY:

Only 4% of patients (365 of 9121) followed ACS guidelines in all four categories.

When assessing adherence to each category, the researchers found that 72% of cancer survivors reported engaging in recommended levels of physical activity, 68% maintained a nonobese weight, 50% said they did not consume alcohol, and 12% said they consumed recommended quantities of fruits and vegetables.

Compared with people in the general population, cancer survivors generally engaged in fewer healthy behaviors than those who had never been diagnosed with cancer.

The authors identified certain factors associated with greater guideline adherence, including female sex, older age, Black (vs White) race, and higher education level (college graduate).

IN PRACTICE:

This study highlights a potential “gap between published guidelines regarding behavioral modifications for cancer survivors and uptake of these behaviors,” the authors wrote, adding that “it is essential for oncologists and general internists to improve widespread and systematic counseling on these guidelines to improve uptake of healthy behaviors in this vulnerable patient population.”

SOURCE:

This work, led by Carter Baughman, MD, from the Division of Internal Medicine at Beth Israel Deaconess Medical Center, Boston, Massachusetts, was published online in JAMA Oncology.

LIMITATIONS:

The authors reported several study limitations, most notably that self-reported data may introduce biases.

DISCLOSURES:

The study funding source was not reported. One author received grants from the US Highbush Blueberry Council outside the submitted work. No other disclosures were reported.

A version of this article appeared on Medscape.com.

TOPLINE:

A recent survey-based study found that only 4% of cancer survivors reported adhering to all four American Cancer Society (ACS) nutrition and physical activity guidelines, which include maintaining a healthy weight and diet, avoiding alcohol, and exercising regularly.

METHODOLOGY:

• The ACS has published nutrition and exercise guidelines for cancer survivors, which include recommendations to maintain a healthy weight and diet, cut out alcohol, and participate in regular physical activities. Engaging in these behaviors is associated with longer survival among cancer survivors, but whether survivors follow these nutrition and activity recommendations has not been systematically tracked.
• Researchers evaluated data on 10,020 individuals (mean age, 64.2 years) who had completed cancer treatment. Data came from the Behavioral Risk Factor Surveillance System telephone-based survey administered in 2017, 2019, and 2021, which represents 2.7 million cancer survivors.
• The researchers estimated survivors’ adherence to guidelines across four domains: Weight, physical activity, fruit and vegetable consumption, and alcohol intake. Factors associated with adherence were also evaluated.
• Overall, 9,121 survivors (91%) completed questionnaires for all four domains.

TAKEAWAY:

Only 4% of patients (365 of 9121) followed ACS guidelines in all four categories.

When assessing adherence to each category, the researchers found that 72% of cancer survivors reported engaging in recommended levels of physical activity, 68% maintained a nonobese weight, 50% said they did not consume alcohol, and 12% said they consumed recommended quantities of fruits and vegetables.

Compared with people in the general population, cancer survivors generally engaged in fewer healthy behaviors than those who had never been diagnosed with cancer.

The authors identified certain factors associated with greater guideline adherence, including female sex, older age, Black (vs White) race, and higher education level (college graduate).

IN PRACTICE:

This study highlights a potential “gap between published guidelines regarding behavioral modifications for cancer survivors and uptake of these behaviors,” the authors wrote, adding that “it is essential for oncologists and general internists to improve widespread and systematic counseling on these guidelines to improve uptake of healthy behaviors in this vulnerable patient population.”

SOURCE:

This work, led by Carter Baughman, MD, from the Division of Internal Medicine at Beth Israel Deaconess Medical Center, Boston, Massachusetts, was published online in JAMA Oncology.

LIMITATIONS:

The authors reported several study limitations, most notably that self-reported data may introduce biases.

DISCLOSURES:

The study funding source was not reported. One author received grants from the US Highbush Blueberry Council outside the submitted work. No other disclosures were reported.

A version of this article appeared on Medscape.com.

New and evolving research in locally advanced rectal cancer suggests that selective use of treatments in some patients can achieve outcomes similar to those of standard regimens, according to the chair of the Department of Radiation Oncology at Duke University School of Medicine, Durham, North Carolina.

Total neoadjuvant therapy (TNT) is the standard treatment that involves systemic chemotherapy and radiation therapy before surgery for patients with locally advanced rectal cancer, Christopher G. Willett, MD, explained, in an interview. However, recent clinical trials support several strategies for “deintensification” of TNT for patients with locally advanced rectal cancer, he said.

Some patients may not require surgery or radiation therapy, or they may not require any treatment modalities including radiation therapy, chemotherapy, and surgery, Dr. Willett continued.

However, “these patients require close surveillance post treatment to identify any recurrence that may require salvage treatment,” he added.

During a presentation at the 2024 National Comprehensive Cancer Network Annual Conference, Dr. Willett primarily discussed the following three strategies for deintensifying overall therapy for locally advanced rectal cancer:

• Selective surgical omission for patients with rectal cancer having a complete clinical response after TNT with close surveillance following treatment.
• Selective omission of radiation therapy for patients with surgery such as sphincter-sparing surgery.
• Selective omission of all treatment modalities (radiation therapy, chemotherapy and surgery). 

Does Watch and Wait Work?

Selective surgical omission, also known as a “watch and wait” or nonoperative management (NOM), involves treating patients with chemotherapy or a combination of chemo and radiation therapy but without surgery, Dr. Willett said during his presentation at the meeting.

Data from the OPRA trial published in the Journal of Clinical Oncology showed that 36% of patients who started on NOM developed tumor regrowth, most of which occurred in the first 2-3 years. Five-year disease-free survival rates were similar in patients who had total mesorectal excision (TME) upfront and those who had salvage TME procedures after tumor regrowth (61% and 62%, respectively). An update to the OPRA trial showed that the clinical outcomes persisted, and the results suggest no significant differences in disease-free survival between upfront surgery vs. watch and wait, Dr. Willett said.
 

Does Selective Omission of Radiotherapy Work?

Selective omission of radiotherapy is another option for reducing the overall treatment burden in patients with locally advanced rectal cancer, Dr. Willett. For these patients, who are at relatively low risk for recurrence, radiation along with surgery may not be needed.

Data from the FOWARC trial, published in the Journal of Clinical Oncology in 2016 and 2019, included 495 patients from 15 centers in China. In the randomized trial, the researchers found no significant difference in the primary outcome of disease-free survival between patients assigned in a 1:1:1 ratio to three arms:

• FOLFOX chemotherapy alone (a combination of chemotherapy drugs including folinic acid, fluorouracil, and oxaliplatin).
• FOLFOX plus chemoradiation.
• FU (fluorouracil)/LV (leucovorin calcium) plus chemoradiation.

Although the data were ultimately inconclusive because of potential staging bias, the findings were “promising for recommending radiation omission in these patients,” Dr. Willett said.

The larger PROSPECT study published in The New England Journal of Medicine in 2023 was similarly encouraging, he said. In this trial, 1194 patients with locally advanced rectal cancer were randomized to FOLFOX or chemoradiation prior to sphincter-sparing surgery. The two groups showed similar 5-year estimated overall survival, complete resection (R0), and pathological complete response.

“These further data support the idea that we don’t need radiotherapy anymore,” Dr. Willett said.

PROSPECT was “a very well-done trial” that also showed important patient reported outcomes, he said. At 12 months after surgery, patients in the chemoradiation group had higher scores on fatigue and neuropathy measures, but less than 15% were severe. Sexual function scores for men and women were worse in the chemoradiation group, although overall health-related quality-of-life scores were not significantly different between the groups, he noted.
 

Does Dropping Everything But Immunotherapy Work?

Research is very preliminary, but a small study of 12 patients with mismatch repair-deficit (MMRd) locally advanced rectal cancer published in The New England Journal of Medicine “lends optimism” to a personalized treatment approach via a programmed death 1 (PD-1) blockade, Dr. Willett said. The “small, but impressive numbers” showed that all 12 patients treated with dostarlimab only (an anti-PD-1 monoclonal antibody) had durable disease control at a follow-up of 6-24 months.

This option is feasible for patients with MMRd locally advanced rectal cancer, Dr. Willett said in an interview. “Patients treated with only dostarlimab (a PD-1 inhibitor) had excellent outcomes and did not require radiation therapy, chemotherapy, and surgery. This is potentially a new paradigm of treatment for MMRd rectal cancer.”

What are the Clinical Implications and Next Steps?

Patients should be carefully evaluated and selected for treatment approaches by experienced multidisciplinary teams with vigilant posttreatment surveillance, including history and physical exam, endoscopy, computed tomography (CT) of the chest, and abdomen and pelvic magnetic resonance imaging (MRI), Dr. Willett said in the interview.

Data on the treatment of patients with MMRd rectal cancer using dostarlimab and other immune checkpoint inhibitors are preliminary; more patients and further follow-up are required, he said. This treatment is applicable to only 5%-10% of patients with rectal cancer, he continued.

“There is a need for biomarkers such as circulating tumor DNA to further aid in selection and monitoring of patients with rectal cancer,” Dr. Willett said.

Other preliminary research is examining circulating tumor DNA analysis to guide adjuvant treatment for patients with resected stage II colon cancer, he noted in his presentation. Currently, ctDNA-driven therapy is not recommended by the NCCN, but more research is needed to determine whether this strategy might be applied to decision-making in rectal cancer patients, especially with watch and wait/nonoperative strategies, he said.
 

What Are the Takeaways for Deintensifying Treatment of Rectal Cancer?

The global continuum of rectal cancer clinical trials has provided significant evidence that, for select patients, the deintensification of treatment strategies may result in the avoidance of radiation and even avoidance of surgery, which can profoundly improve long-term quality of life, Al B. Benson III, MD, said in an interview.

“A critical takeaway message for clinicians who are determining which individual patient might benefit from a less intensive regimen to treat locally advanced rectal cancer is to first have a multidisciplinary consensus which should encompass review of a rectal MRI, pathology, chest and abdominal imaging, colonoscopy, as well as the patient’s clinical status including comorbidities,” said Dr. Benson, who served as chair of the NCCN Guidelines Panel for Colon/Rectal/Anal Cancers and Small Intestine Adenocarcinoma.

“The location of the rectal tumor (distal versus proximal) and clinical TNM stage also will inform the discussion as to which of the potential total neoadjuvant therapy regimens would be most optimal to reduce the risk of local recurrence and maintain long-term quality of life for the individual patient,” explained Dr. Benson, professor of medicine at Robert H. Lurie Comprehensive Cancer Center of Northwestern University in Chicago.

The effectiveness of less intense treatment for rectal cancer remains a work in progress, Dr. Benson said in an interview. “There is much we still do not know, such as the optimal selection of patients and the durability of this approach over time.”

Patients who undergo watch and wait require intensive follow-up, including sigmoidoscopy, digital rectal exam, and rectal MRI, to detect any evidence of local recurrence that would warrant further intervention, including possible radiation and surgery, he said. A highly skilled multidisciplinary team is a must for individuals who are potential candidates for a less intense treatment regimen, he emphasized.  

The treatment of locally advanced rectal cancer continues to evolve, but there is no question that TNT has transformed patient outcomes, including the ability to deintensify treatment for select patients, Dr. Benson said. 

However, many research gaps remain, Dr. Benson said in an interview. “For the MSI/dMMR patient who has achieved a complete response from immunotherapy we will need more long-term data to determine the durability of a complete clinical response and long-term avoidance of other interventions including radiation, chemotherapy and surgery.

“The wait and watch strategy for the much more common MSS patient also will require much longer follow-up to determine which patients are destined to recur and which are not,” he added.

“The introduction of monitoring with ctDNA determination over time offers an opportunity to streamline surveillance of patients who have completed combination therapy and for those undergoing watch and wait; however, much more information is required to determine which of the various ctDNA assays are most optimal, and the frequency and duration of ctDNA determination that will lend this approach as a standard of care,” Dr. Benson said.

Dr. Willett and Dr. Benson had no financial conflicts to disclose.

New and evolving research in locally advanced rectal cancer suggests that selective use of treatments in some patients can achieve outcomes similar to those of standard regimens, according to the chair of the Department of Radiation Oncology at Duke University School of Medicine, Durham, North Carolina.

Total neoadjuvant therapy (TNT) is the standard treatment that involves systemic chemotherapy and radiation therapy before surgery for patients with locally advanced rectal cancer, Christopher G. Willett, MD, explained, in an interview. However, recent clinical trials support several strategies for “deintensification” of TNT for patients with locally advanced rectal cancer, he said.

Some patients may not require surgery or radiation therapy, or they may not require any treatment modalities including radiation therapy, chemotherapy, and surgery, Dr. Willett continued.

However, “these patients require close surveillance post treatment to identify any recurrence that may require salvage treatment,” he added.

During a presentation at the 2024 National Comprehensive Cancer Network Annual Conference, Dr. Willett primarily discussed the following three strategies for deintensifying overall therapy for locally advanced rectal cancer:

• Selective surgical omission for patients with rectal cancer having a complete clinical response after TNT with close surveillance following treatment.
• Selective omission of radiation therapy for patients with surgery such as sphincter-sparing surgery.
• Selective omission of all treatment modalities (radiation therapy, chemotherapy and surgery). 

Does Watch and Wait Work?

Selective surgical omission, also known as a “watch and wait” or nonoperative management (NOM), involves treating patients with chemotherapy or a combination of chemo and radiation therapy but without surgery, Dr. Willett said during his presentation at the meeting.

Data from the OPRA trial published in the Journal of Clinical Oncology showed that 36% of patients who started on NOM developed tumor regrowth, most of which occurred in the first 2-3 years. Five-year disease-free survival rates were similar in patients who had total mesorectal excision (TME) upfront and those who had salvage TME procedures after tumor regrowth (61% and 62%, respectively). An update to the OPRA trial showed that the clinical outcomes persisted, and the results suggest no significant differences in disease-free survival between upfront surgery vs. watch and wait, Dr. Willett said.
 

Does Selective Omission of Radiotherapy Work?

Selective omission of radiotherapy is another option for reducing the overall treatment burden in patients with locally advanced rectal cancer, Dr. Willett. For these patients, who are at relatively low risk for recurrence, radiation along with surgery may not be needed.

Data from the FOWARC trial, published in the Journal of Clinical Oncology in 2016 and 2019, included 495 patients from 15 centers in China. In the randomized trial, the researchers found no significant difference in the primary outcome of disease-free survival between patients assigned in a 1:1:1 ratio to three arms:

• FOLFOX chemotherapy alone (a combination of chemotherapy drugs including folinic acid, fluorouracil, and oxaliplatin).
• FOLFOX plus chemoradiation.
• FU (fluorouracil)/LV (leucovorin calcium) plus chemoradiation.

Although the data were ultimately inconclusive because of potential staging bias, the findings were “promising for recommending radiation omission in these patients,” Dr. Willett said.

The larger PROSPECT study published in The New England Journal of Medicine in 2023 was similarly encouraging, he said. In this trial, 1194 patients with locally advanced rectal cancer were randomized to FOLFOX or chemoradiation prior to sphincter-sparing surgery. The two groups showed similar 5-year estimated overall survival, complete resection (R0), and pathological complete response.

“These further data support the idea that we don’t need radiotherapy anymore,” Dr. Willett said.

PROSPECT was “a very well-done trial” that also showed important patient reported outcomes, he said. At 12 months after surgery, patients in the chemoradiation group had higher scores on fatigue and neuropathy measures, but less than 15% were severe. Sexual function scores for men and women were worse in the chemoradiation group, although overall health-related quality-of-life scores were not significantly different between the groups, he noted.
 

Does Dropping Everything But Immunotherapy Work?

Research is very preliminary, but a small study of 12 patients with mismatch repair-deficit (MMRd) locally advanced rectal cancer published in The New England Journal of Medicine “lends optimism” to a personalized treatment approach via a programmed death 1 (PD-1) blockade, Dr. Willett said. The “small, but impressive numbers” showed that all 12 patients treated with dostarlimab only (an anti-PD-1 monoclonal antibody) had durable disease control at a follow-up of 6-24 months.

This option is feasible for patients with MMRd locally advanced rectal cancer, Dr. Willett said in an interview. “Patients treated with only dostarlimab (a PD-1 inhibitor) had excellent outcomes and did not require radiation therapy, chemotherapy, and surgery. This is potentially a new paradigm of treatment for MMRd rectal cancer.”

What are the Clinical Implications and Next Steps?

Patients should be carefully evaluated and selected for treatment approaches by experienced multidisciplinary teams with vigilant posttreatment surveillance, including history and physical exam, endoscopy, computed tomography (CT) of the chest, and abdomen and pelvic magnetic resonance imaging (MRI), Dr. Willett said in the interview.

Data on the treatment of patients with MMRd rectal cancer using dostarlimab and other immune checkpoint inhibitors are preliminary; more patients and further follow-up are required, he said. This treatment is applicable to only 5%-10% of patients with rectal cancer, he continued.

“There is a need for biomarkers such as circulating tumor DNA to further aid in selection and monitoring of patients with rectal cancer,” Dr. Willett said.

Other preliminary research is examining circulating tumor DNA analysis to guide adjuvant treatment for patients with resected stage II colon cancer, he noted in his presentation. Currently, ctDNA-driven therapy is not recommended by the NCCN, but more research is needed to determine whether this strategy might be applied to decision-making in rectal cancer patients, especially with watch and wait/nonoperative strategies, he said.
 

What Are the Takeaways for Deintensifying Treatment of Rectal Cancer?

The global continuum of rectal cancer clinical trials has provided significant evidence that, for select patients, the deintensification of treatment strategies may result in the avoidance of radiation and even avoidance of surgery, which can profoundly improve long-term quality of life, Al B. Benson III, MD, said in an interview.

“A critical takeaway message for clinicians who are determining which individual patient might benefit from a less intensive regimen to treat locally advanced rectal cancer is to first have a multidisciplinary consensus which should encompass review of a rectal MRI, pathology, chest and abdominal imaging, colonoscopy, as well as the patient’s clinical status including comorbidities,” said Dr. Benson, who served as chair of the NCCN Guidelines Panel for Colon/Rectal/Anal Cancers and Small Intestine Adenocarcinoma.

“The location of the rectal tumor (distal versus proximal) and clinical TNM stage also will inform the discussion as to which of the potential total neoadjuvant therapy regimens would be most optimal to reduce the risk of local recurrence and maintain long-term quality of life for the individual patient,” explained Dr. Benson, professor of medicine at Robert H. Lurie Comprehensive Cancer Center of Northwestern University in Chicago.

The effectiveness of less intense treatment for rectal cancer remains a work in progress, Dr. Benson said in an interview. “There is much we still do not know, such as the optimal selection of patients and the durability of this approach over time.”

Patients who undergo watch and wait require intensive follow-up, including sigmoidoscopy, digital rectal exam, and rectal MRI, to detect any evidence of local recurrence that would warrant further intervention, including possible radiation and surgery, he said. A highly skilled multidisciplinary team is a must for individuals who are potential candidates for a less intense treatment regimen, he emphasized.  

The treatment of locally advanced rectal cancer continues to evolve, but there is no question that TNT has transformed patient outcomes, including the ability to deintensify treatment for select patients, Dr. Benson said. 

However, many research gaps remain, Dr. Benson said in an interview. “For the MSI/dMMR patient who has achieved a complete response from immunotherapy we will need more long-term data to determine the durability of a complete clinical response and long-term avoidance of other interventions including radiation, chemotherapy and surgery.

“The wait and watch strategy for the much more common MSS patient also will require much longer follow-up to determine which patients are destined to recur and which are not,” he added.

“The introduction of monitoring with ctDNA determination over time offers an opportunity to streamline surveillance of patients who have completed combination therapy and for those undergoing watch and wait; however, much more information is required to determine which of the various ctDNA assays are most optimal, and the frequency and duration of ctDNA determination that will lend this approach as a standard of care,” Dr. Benson said.

Dr. Willett and Dr. Benson had no financial conflicts to disclose.

New and evolving research in locally advanced rectal cancer suggests that selective use of treatments in some patients can achieve outcomes similar to those of standard regimens, according to the chair of the Department of Radiation Oncology at Duke University School of Medicine, Durham, North Carolina.

Total neoadjuvant therapy (TNT) is the standard treatment that involves systemic chemotherapy and radiation therapy before surgery for patients with locally advanced rectal cancer, Christopher G. Willett, MD, explained, in an interview. However, recent clinical trials support several strategies for “deintensification” of TNT for patients with locally advanced rectal cancer, he said.

Some patients may not require surgery or radiation therapy, or they may not require any treatment modalities including radiation therapy, chemotherapy, and surgery, Dr. Willett continued.

However, “these patients require close surveillance post treatment to identify any recurrence that may require salvage treatment,” he added.

During a presentation at the 2024 National Comprehensive Cancer Network Annual Conference, Dr. Willett primarily discussed the following three strategies for deintensifying overall therapy for locally advanced rectal cancer:

• Selective surgical omission for patients with rectal cancer having a complete clinical response after TNT with close surveillance following treatment.
• Selective omission of radiation therapy for patients with surgery such as sphincter-sparing surgery.
• Selective omission of all treatment modalities (radiation therapy, chemotherapy and surgery). 

Does Watch and Wait Work?

Selective surgical omission, also known as a “watch and wait” or nonoperative management (NOM), involves treating patients with chemotherapy or a combination of chemo and radiation therapy but without surgery, Dr. Willett said during his presentation at the meeting.

Data from the OPRA trial published in the Journal of Clinical Oncology showed that 36% of patients who started on NOM developed tumor regrowth, most of which occurred in the first 2-3 years. Five-year disease-free survival rates were similar in patients who had total mesorectal excision (TME) upfront and those who had salvage TME procedures after tumor regrowth (61% and 62%, respectively). An update to the OPRA trial showed that the clinical outcomes persisted, and the results suggest no significant differences in disease-free survival between upfront surgery vs. watch and wait, Dr. Willett said.
 

Does Selective Omission of Radiotherapy Work?

Selective omission of radiotherapy is another option for reducing the overall treatment burden in patients with locally advanced rectal cancer, Dr. Willett. For these patients, who are at relatively low risk for recurrence, radiation along with surgery may not be needed.

Data from the FOWARC trial, published in the Journal of Clinical Oncology in 2016 and 2019, included 495 patients from 15 centers in China. In the randomized trial, the researchers found no significant difference in the primary outcome of disease-free survival between patients assigned in a 1:1:1 ratio to three arms:

• FOLFOX chemotherapy alone (a combination of chemotherapy drugs including folinic acid, fluorouracil, and oxaliplatin).
• FOLFOX plus chemoradiation.
• FU (fluorouracil)/LV (leucovorin calcium) plus chemoradiation.

Although the data were ultimately inconclusive because of potential staging bias, the findings were “promising for recommending radiation omission in these patients,” Dr. Willett said.

The larger PROSPECT study published in The New England Journal of Medicine in 2023 was similarly encouraging, he said. In this trial, 1194 patients with locally advanced rectal cancer were randomized to FOLFOX or chemoradiation prior to sphincter-sparing surgery. The two groups showed similar 5-year estimated overall survival, complete resection (R0), and pathological complete response.

“These further data support the idea that we don’t need radiotherapy anymore,” Dr. Willett said.

PROSPECT was “a very well-done trial” that also showed important patient reported outcomes, he said. At 12 months after surgery, patients in the chemoradiation group had higher scores on fatigue and neuropathy measures, but less than 15% were severe. Sexual function scores for men and women were worse in the chemoradiation group, although overall health-related quality-of-life scores were not significantly different between the groups, he noted.
 

Does Dropping Everything But Immunotherapy Work?

Research is very preliminary, but a small study of 12 patients with mismatch repair-deficit (MMRd) locally advanced rectal cancer published in The New England Journal of Medicine “lends optimism” to a personalized treatment approach via a programmed death 1 (PD-1) blockade, Dr. Willett said. The “small, but impressive numbers” showed that all 12 patients treated with dostarlimab only (an anti-PD-1 monoclonal antibody) had durable disease control at a follow-up of 6-24 months.

This option is feasible for patients with MMRd locally advanced rectal cancer, Dr. Willett said in an interview. “Patients treated with only dostarlimab (a PD-1 inhibitor) had excellent outcomes and did not require radiation therapy, chemotherapy, and surgery. This is potentially a new paradigm of treatment for MMRd rectal cancer.”

What are the Clinical Implications and Next Steps?

Patients should be carefully evaluated and selected for treatment approaches by experienced multidisciplinary teams with vigilant posttreatment surveillance, including history and physical exam, endoscopy, computed tomography (CT) of the chest, and abdomen and pelvic magnetic resonance imaging (MRI), Dr. Willett said in the interview.

Data on the treatment of patients with MMRd rectal cancer using dostarlimab and other immune checkpoint inhibitors are preliminary; more patients and further follow-up are required, he said. This treatment is applicable to only 5%-10% of patients with rectal cancer, he continued.

“There is a need for biomarkers such as circulating tumor DNA to further aid in selection and monitoring of patients with rectal cancer,” Dr. Willett said.

Other preliminary research is examining circulating tumor DNA analysis to guide adjuvant treatment for patients with resected stage II colon cancer, he noted in his presentation. Currently, ctDNA-driven therapy is not recommended by the NCCN, but more research is needed to determine whether this strategy might be applied to decision-making in rectal cancer patients, especially with watch and wait/nonoperative strategies, he said.
 

What Are the Takeaways for Deintensifying Treatment of Rectal Cancer?

The global continuum of rectal cancer clinical trials has provided significant evidence that, for select patients, the deintensification of treatment strategies may result in the avoidance of radiation and even avoidance of surgery, which can profoundly improve long-term quality of life, Al B. Benson III, MD, said in an interview.

“A critical takeaway message for clinicians who are determining which individual patient might benefit from a less intensive regimen to treat locally advanced rectal cancer is to first have a multidisciplinary consensus which should encompass review of a rectal MRI, pathology, chest and abdominal imaging, colonoscopy, as well as the patient’s clinical status including comorbidities,” said Dr. Benson, who served as chair of the NCCN Guidelines Panel for Colon/Rectal/Anal Cancers and Small Intestine Adenocarcinoma.

“The location of the rectal tumor (distal versus proximal) and clinical TNM stage also will inform the discussion as to which of the potential total neoadjuvant therapy regimens would be most optimal to reduce the risk of local recurrence and maintain long-term quality of life for the individual patient,” explained Dr. Benson, professor of medicine at Robert H. Lurie Comprehensive Cancer Center of Northwestern University in Chicago.

The effectiveness of less intense treatment for rectal cancer remains a work in progress, Dr. Benson said in an interview. “There is much we still do not know, such as the optimal selection of patients and the durability of this approach over time.”

Patients who undergo watch and wait require intensive follow-up, including sigmoidoscopy, digital rectal exam, and rectal MRI, to detect any evidence of local recurrence that would warrant further intervention, including possible radiation and surgery, he said. A highly skilled multidisciplinary team is a must for individuals who are potential candidates for a less intense treatment regimen, he emphasized.  

The treatment of locally advanced rectal cancer continues to evolve, but there is no question that TNT has transformed patient outcomes, including the ability to deintensify treatment for select patients, Dr. Benson said. 

However, many research gaps remain, Dr. Benson said in an interview. “For the MSI/dMMR patient who has achieved a complete response from immunotherapy we will need more long-term data to determine the durability of a complete clinical response and long-term avoidance of other interventions including radiation, chemotherapy and surgery.

“The wait and watch strategy for the much more common MSS patient also will require much longer follow-up to determine which patients are destined to recur and which are not,” he added.

“The introduction of monitoring with ctDNA determination over time offers an opportunity to streamline surveillance of patients who have completed combination therapy and for those undergoing watch and wait; however, much more information is required to determine which of the various ctDNA assays are most optimal, and the frequency and duration of ctDNA determination that will lend this approach as a standard of care,” Dr. Benson said.

Dr. Willett and Dr. Benson had no financial conflicts to disclose.

Last year, I concluded a commentary for this news organization on colorectal cancer (CRC) screening guidelines by stating that between stool-based tests, flexible sigmoidoscopy, and colonoscopy, “the best screening test is the test that gets done.” But should that maxim apply to the new blood-based screening test, Guardant Health Shield? This proprietary test, which costs $895 and is not generally covered by insurance, identifies alterations in cell-free DNA that are characteristic of CRC.

Shield’s test characteristics were recently evaluated in a prospective study of more than 10,000 adults aged 45-84 at average risk for CRC. The test had an 87.5% sensitivity for stage I, II, or III colorectal cancer but only a 13% sensitivity for advanced precancerous lesions. Test specificity was 89.6%, meaning that about 1 in 10 participants without CRC or advanced precancerous lesions on colonoscopy had a false-positive result.

Although the Shield blood test has a higher rate of false positives than the traditional fecal immunochemical test (FIT) and lower sensitivity and specificity than a multitarget stool DNA (FIT-DNA) test designed to improve on Cologuard, it meets the previously established criteria set forth by the Centers for Medicare & Medicaid Services (CMS) to be covered for Medicare beneficiaries at 3-year intervals, pending FDA approval. If public and private payers start covering Shield alongside other CRC screening tests, it presents an opportunity for primary care physicians to reach the approximately 3 in 10 adults between ages 45 and 75 who are not being routinely screened.

A big concern, however, is that the availability of a blood test may cause patients who would have otherwise been screened with colonoscopy or stool tests to switch to the blood test. A cost-effectiveness analysis found that offering a blood test to patients who decline screening colonoscopy saves additional lives, but at the cost of more than $377,000 per life-year gained. Another study relying on three microsimulation models previously utilized by the US Preventive Services Task Force (USPSTF) found that annual FIT results in more life-years gained at substantially lower cost than blood-based screening every 3 years “even when uptake of blood-based screening was 20 percentage points higher than uptake of FIT.” As a result, a multidisciplinary expert panel concluded that blood-based screening should not substitute for established CRC screening tests, but instead be offered only to patients who decline those tests.

In practice, this will increase the complexity of the CRC screening conversations we have with patients. We will need to be clear that the blood test is not yet endorsed by the USPSTF or any major guideline group and is a second-line test that will miss most precancerous polyps. As with the stool tests, it is essential to emphasize that a positive result must be followed by diagnostic colonoscopy. To addend the cancer screening maxim I mentioned before, the blood test is not the best test for CRC, but it’s probably better than no test at all.

Dr. Lin is a family physician and associate director, Family Medicine Residency Program, Lancaster General Hospital, Lancaster, Pennsylvania. He blogs at Common Sense Family Doctor.

A version of this article appeared on Medscape.com.

Last year, I concluded a commentary for this news organization on colorectal cancer (CRC) screening guidelines by stating that between stool-based tests, flexible sigmoidoscopy, and colonoscopy, “the best screening test is the test that gets done.” But should that maxim apply to the new blood-based screening test, Guardant Health Shield? This proprietary test, which costs $895 and is not generally covered by insurance, identifies alterations in cell-free DNA that are characteristic of CRC.

Shield’s test characteristics were recently evaluated in a prospective study of more than 10,000 adults aged 45-84 at average risk for CRC. The test had an 87.5% sensitivity for stage I, II, or III colorectal cancer but only a 13% sensitivity for advanced precancerous lesions. Test specificity was 89.6%, meaning that about 1 in 10 participants without CRC or advanced precancerous lesions on colonoscopy had a false-positive result.

Although the Shield blood test has a higher rate of false positives than the traditional fecal immunochemical test (FIT) and lower sensitivity and specificity than a multitarget stool DNA (FIT-DNA) test designed to improve on Cologuard, it meets the previously established criteria set forth by the Centers for Medicare & Medicaid Services (CMS) to be covered for Medicare beneficiaries at 3-year intervals, pending FDA approval. If public and private payers start covering Shield alongside other CRC screening tests, it presents an opportunity for primary care physicians to reach the approximately 3 in 10 adults between ages 45 and 75 who are not being routinely screened.

A big concern, however, is that the availability of a blood test may cause patients who would have otherwise been screened with colonoscopy or stool tests to switch to the blood test. A cost-effectiveness analysis found that offering a blood test to patients who decline screening colonoscopy saves additional lives, but at the cost of more than $377,000 per life-year gained. Another study relying on three microsimulation models previously utilized by the US Preventive Services Task Force (USPSTF) found that annual FIT results in more life-years gained at substantially lower cost than blood-based screening every 3 years “even when uptake of blood-based screening was 20 percentage points higher than uptake of FIT.” As a result, a multidisciplinary expert panel concluded that blood-based screening should not substitute for established CRC screening tests, but instead be offered only to patients who decline those tests.

In practice, this will increase the complexity of the CRC screening conversations we have with patients. We will need to be clear that the blood test is not yet endorsed by the USPSTF or any major guideline group and is a second-line test that will miss most precancerous polyps. As with the stool tests, it is essential to emphasize that a positive result must be followed by diagnostic colonoscopy. To addend the cancer screening maxim I mentioned before, the blood test is not the best test for CRC, but it’s probably better than no test at all.

Dr. Lin is a family physician and associate director, Family Medicine Residency Program, Lancaster General Hospital, Lancaster, Pennsylvania. He blogs at Common Sense Family Doctor.

A version of this article appeared on Medscape.com.

Last year, I concluded a commentary for this news organization on colorectal cancer (CRC) screening guidelines by stating that between stool-based tests, flexible sigmoidoscopy, and colonoscopy, “the best screening test is the test that gets done.” But should that maxim apply to the new blood-based screening test, Guardant Health Shield? This proprietary test, which costs $895 and is not generally covered by insurance, identifies alterations in cell-free DNA that are characteristic of CRC.

Shield’s test characteristics were recently evaluated in a prospective study of more than 10,000 adults aged 45-84 at average risk for CRC. The test had an 87.5% sensitivity for stage I, II, or III colorectal cancer but only a 13% sensitivity for advanced precancerous lesions. Test specificity was 89.6%, meaning that about 1 in 10 participants without CRC or advanced precancerous lesions on colonoscopy had a false-positive result.

Although the Shield blood test has a higher rate of false positives than the traditional fecal immunochemical test (FIT) and lower sensitivity and specificity than a multitarget stool DNA (FIT-DNA) test designed to improve on Cologuard, it meets the previously established criteria set forth by the Centers for Medicare & Medicaid Services (CMS) to be covered for Medicare beneficiaries at 3-year intervals, pending FDA approval. If public and private payers start covering Shield alongside other CRC screening tests, it presents an opportunity for primary care physicians to reach the approximately 3 in 10 adults between ages 45 and 75 who are not being routinely screened.

A big concern, however, is that the availability of a blood test may cause patients who would have otherwise been screened with colonoscopy or stool tests to switch to the blood test. A cost-effectiveness analysis found that offering a blood test to patients who decline screening colonoscopy saves additional lives, but at the cost of more than $377,000 per life-year gained. Another study relying on three microsimulation models previously utilized by the US Preventive Services Task Force (USPSTF) found that annual FIT results in more life-years gained at substantially lower cost than blood-based screening every 3 years “even when uptake of blood-based screening was 20 percentage points higher than uptake of FIT.” As a result, a multidisciplinary expert panel concluded that blood-based screening should not substitute for established CRC screening tests, but instead be offered only to patients who decline those tests.

In practice, this will increase the complexity of the CRC screening conversations we have with patients. We will need to be clear that the blood test is not yet endorsed by the USPSTF or any major guideline group and is a second-line test that will miss most precancerous polyps. As with the stool tests, it is essential to emphasize that a positive result must be followed by diagnostic colonoscopy. To addend the cancer screening maxim I mentioned before, the blood test is not the best test for CRC, but it’s probably better than no test at all.

Dr. Lin is a family physician and associate director, Family Medicine Residency Program, Lancaster General Hospital, Lancaster, Pennsylvania. He blogs at Common Sense Family Doctor.

A version of this article appeared on Medscape.com.

The latest research supports immune checkpoint inhibitor therapy for clear cell and non–clear cell renal cell carcinoma, but patient selection is key to optimize outcomes, according to a medical oncologist from the Dana-Farber Cancer Institute, Boston.

Michael Serzan, MD, who works in the Lank Center for Genitourinary Oncology at the institute, stated this at the 2024 National Comprehensive Cancer Network Annual Conference, during a presentation.

A systematic review and meta-analysis published in 2022 in European Urology Open Science summarized six randomized controlled trials with a total of 5121 adult patients. In the review, the researchers found that immune checkpoint inhibitors plus vascular endothelial growth factor tyrosine kinase inhibitors (VEGF TKI) were associated with consistent improvements across all risk groups for metastatic renal cell carcinoma.

Additional newer research supports the use of immunotherapy combinations or other immunotherapy plus tyrosine kinase inhibitors as first-line or adjuvant treatments for renal cell carcinoma, Dr. Serzan said during an interview. However, more genomic and histology-directed therapies are needed, he noted.
 

Tips for Evaluating Risk When Treating Renal Cell Carcinoma?

For patients with localized clear cell renal cell carcinoma who have undergone partial or radical nephrectomy, there are several models that estimate the risk of recurrence based on pathologic tumor stage, grade, histology, invasion, and the extent of necrosis, Dr. Serzan said. These models can help guide selection of patients who may be at high risk of recurrence and, therefore, may benefit from adjuvant therapy.

For patients with metastatic clear cell renal cell carcinoma, the IMDC and MSKCC prognostic models stratify patients to favorable, intermediate, and poor risk groups based on clinical and lab factors. The IMDC risk stratification model is used as a prognostic model to stratify patients diagnosed with metastatic kidney cancer, Dr. Serzan said.
 

What Research Supports Treatments for Clear Cell and Non–Clear Cell Renal Cell Carcinoma?

The US Food and Drug Administration (FDA) approved pembrolizumab in 2021 for the adjuvant treatment of renal cell carcinoma (RCC) in patients with intermediate-risk or high-risk of recurrence after nephrectomy or after nephrectomy and resection of metastatic lesions.

Pembrolizumab is the first adjuvant therapy shown to significantly improve overall survival in these patients, Dr. Serzan said. In the KEYNOTE-564 study, published in 2024 in the Journal of Clinical Oncology, pembrolizumab demonstrated an improvement in disease free survival as well as overall survival when compared with placebo.

Several similar studies of adjuvant immune checkpoint inhibitors for renal cell carcinoma involving atezolizumab vs. placebo, nivolumab plus ipilimumab vs. placebo, and nivolumab vs. observation have not shown significant benefits in terms of disease-free survival, Dr. Serzan noted.

The current NCCN Clinical Practice Guidelines in Oncology for Kidney Cancer (Version: 3.2024), which were updated this year, support the use of adjuvant pembrolizumab for patients with stage II, III, or IV clear cell renal cell carcinoma after partial or radical nephrectomy, he said.

Looking ahead, biomarkers are needed to understand the risk of recurrence, and which patients benefit from adjuvant pembrolizumab, Dr. Serzan added.
 

Where Do VEGF-TKIs Fit In?

VEGF is a treatment target for renal cancer, and angiogenesis inhibition with VEGF TKIs continues to be a subject for study, Dr. Serzan said. In the CABOSUN study, published in the Journal of Clinical Oncology in 2017, patients were randomized to cabozantinib or sunitinib. Progression-free survival was significantly greater in the cabozantinib group, but overall survival was similar between the groups.

In another randomized trial, the CheckMate 214 study, patients received either sunitinib or a combination of nivolumab plus ipilimumab in four doses given every 3 weeks, followed by nivolumab alone every 2 weeks, and these patients were stratified by risk, Dr. Serzan noted.

The median progression-free survival was 12.4 months in the combination group vs. 8.5 months in the sunitinib group for patients at intermediate or poor risk of recurrence. The median progression-free survival was significantly greater in sunitinib patients with favorable risk vs. combination patients with favorable risk (28.9 months vs. 12.4 months).

Overall survival was higher for all patients with combination therapy vs. sunitinib regardless of risk stratification.

Dr. Serzan reviewed the pros of VEGF/PD1 (programmed death-ligand 1) combinations as including a high response rate (generally 52%-72%) and a low rate of primary progressive disease (5%-12%), as well as favorable progression-free and overall survival and low rates of immune-related adverse events.

However, cons of this treatment include lack of data on treatment-free survival as well as the decrease in progression-free survival and overall survival hazard ratios over time and potential chronic VEGF/TKI toxicities, he said.
 

What Treatments Are Recommended for Metastatic Clear Cell Renal Cell Carcinoma Now?

Clear cell renal cell carcinoma (ccRCC) is the most prevalent histological subtype of kidney cancer, accounting for 70%-75% of cases, and these patients are prone to metastasis, recurrence, and resistance to radiotherapy and chemotherapy, according to authors of a recent review published in Frontiers in Oncology.

Dr. Serzan shared his preferred protocol for treatment-naive metastatic ccRCC patients, based on the NCCN guidelines for Kidney Cancer (Version: 3.2024) that had been updated in 2024.

For those with sarcomatoid features, he favors the use of nivolumab/ipilimumab combination, while those without sarcomatoid features, if highly symptomatic, may be treated with any of several combinations: nivolumab/ipilimumab, axitinib/pembrolizumab, cabozantinib/nivolumab, or lenvatinib/pembrolizumab.

For asymptomatic patients without sarcomatoid features, treatment depends on eligibility for immune checkpoint inhibitors or ipilimumab, Dr. Serzan said. His first choice for those eligible is nivolumab/ipilimumab; those not eligible for ipilimumab could receive nivolumab, pembrolizumab, axitinib/pembrolizumab, cabozantinib/nivolumab, or lenvatinib/pembrolizumab.

For patients not eligible for ICIs because of uncontrolled autoimmune disease, or high-dose glucocorticoids, Dr. Serzan recommended treatment with cabozantinib, lenvatinib/everolimus, pazopanib, or sunitinib.
 

What are Some Takeaway Points About Immunotherapy and Renal Cell Carcinoma?

“Immunotherapy has revolutionized treatment for renal cell carcinoma, with significant increases in overall survival, and a small but consistent cure fraction that was unimaginable 10 years ago,” Eric Jonasch, MD, of The University of Texas MD Anderson Cancer Center and vice-chair of the NCCN Guidelines Panel for Kidney Cancer, said in an interview.

However, challenges to implementing new treatments in clinical practice are ongoing, he said. The major challenges facing clinicians, patients, and their families include the cost of therapy, logistics of treatment administration, and managing toxicities, Dr. Jonasch said.  

Patient selection is key to optimize outcomes with immunotherapy, and shared decision-making is essential to ensure that choice of therapy matches patient expectations and needs — and to maintain clear and open channels of communication while patients are on therapy, Dr. Jonasch said. “In my clinic, we empower patients to take treatment breaks to manage side effects, thereby optimizing quality of life while maintaining treatment efficacy,” he said.

Although significant progress has been made in managing renal cell carcinoma, more research is needed to increase the proportion of patients cured, said Dr. Jonasch. “A clearer understanding of the determinants of response and resistance, which will be driven by information rich clinical trials, will help move us in that direction,” he said.

Dr. Serzan had no financial conflicts to disclose. Dr. Jonasch disclosed research support from AbbVie, Arrowhead, Aveo, BMS, Corvus, Merck, NiKang, ProfoundBio, and Telix, as well as honoraria from Aveo, Eisai, Exelixis, GlaxoSmithKline, Ipsen, Merck, Novartis, NiKang, and Takeda.

The latest research supports immune checkpoint inhibitor therapy for clear cell and non–clear cell renal cell carcinoma, but patient selection is key to optimize outcomes, according to a medical oncologist from the Dana-Farber Cancer Institute, Boston.

Michael Serzan, MD, who works in the Lank Center for Genitourinary Oncology at the institute, stated this at the 2024 National Comprehensive Cancer Network Annual Conference, during a presentation.

A systematic review and meta-analysis published in 2022 in European Urology Open Science summarized six randomized controlled trials with a total of 5121 adult patients. In the review, the researchers found that immune checkpoint inhibitors plus vascular endothelial growth factor tyrosine kinase inhibitors (VEGF TKI) were associated with consistent improvements across all risk groups for metastatic renal cell carcinoma.

Additional newer research supports the use of immunotherapy combinations or other immunotherapy plus tyrosine kinase inhibitors as first-line or adjuvant treatments for renal cell carcinoma, Dr. Serzan said during an interview. However, more genomic and histology-directed therapies are needed, he noted.
 

Tips for Evaluating Risk When Treating Renal Cell Carcinoma?

For patients with localized clear cell renal cell carcinoma who have undergone partial or radical nephrectomy, there are several models that estimate the risk of recurrence based on pathologic tumor stage, grade, histology, invasion, and the extent of necrosis, Dr. Serzan said. These models can help guide selection of patients who may be at high risk of recurrence and, therefore, may benefit from adjuvant therapy.

For patients with metastatic clear cell renal cell carcinoma, the IMDC and MSKCC prognostic models stratify patients to favorable, intermediate, and poor risk groups based on clinical and lab factors. The IMDC risk stratification model is used as a prognostic model to stratify patients diagnosed with metastatic kidney cancer, Dr. Serzan said.
 

What Research Supports Treatments for Clear Cell and Non–Clear Cell Renal Cell Carcinoma?

The US Food and Drug Administration (FDA) approved pembrolizumab in 2021 for the adjuvant treatment of renal cell carcinoma (RCC) in patients with intermediate-risk or high-risk of recurrence after nephrectomy or after nephrectomy and resection of metastatic lesions.

Pembrolizumab is the first adjuvant therapy shown to significantly improve overall survival in these patients, Dr. Serzan said. In the KEYNOTE-564 study, published in 2024 in the Journal of Clinical Oncology, pembrolizumab demonstrated an improvement in disease free survival as well as overall survival when compared with placebo.

Several similar studies of adjuvant immune checkpoint inhibitors for renal cell carcinoma involving atezolizumab vs. placebo, nivolumab plus ipilimumab vs. placebo, and nivolumab vs. observation have not shown significant benefits in terms of disease-free survival, Dr. Serzan noted.

The current NCCN Clinical Practice Guidelines in Oncology for Kidney Cancer (Version: 3.2024), which were updated this year, support the use of adjuvant pembrolizumab for patients with stage II, III, or IV clear cell renal cell carcinoma after partial or radical nephrectomy, he said.

Looking ahead, biomarkers are needed to understand the risk of recurrence, and which patients benefit from adjuvant pembrolizumab, Dr. Serzan added.
 

Where Do VEGF-TKIs Fit In?

VEGF is a treatment target for renal cancer, and angiogenesis inhibition with VEGF TKIs continues to be a subject for study, Dr. Serzan said. In the CABOSUN study, published in the Journal of Clinical Oncology in 2017, patients were randomized to cabozantinib or sunitinib. Progression-free survival was significantly greater in the cabozantinib group, but overall survival was similar between the groups.

In another randomized trial, the CheckMate 214 study, patients received either sunitinib or a combination of nivolumab plus ipilimumab in four doses given every 3 weeks, followed by nivolumab alone every 2 weeks, and these patients were stratified by risk, Dr. Serzan noted.

The median progression-free survival was 12.4 months in the combination group vs. 8.5 months in the sunitinib group for patients at intermediate or poor risk of recurrence. The median progression-free survival was significantly greater in sunitinib patients with favorable risk vs. combination patients with favorable risk (28.9 months vs. 12.4 months).

Overall survival was higher for all patients with combination therapy vs. sunitinib regardless of risk stratification.

Dr. Serzan reviewed the pros of VEGF/PD1 (programmed death-ligand 1) combinations as including a high response rate (generally 52%-72%) and a low rate of primary progressive disease (5%-12%), as well as favorable progression-free and overall survival and low rates of immune-related adverse events.

However, cons of this treatment include lack of data on treatment-free survival as well as the decrease in progression-free survival and overall survival hazard ratios over time and potential chronic VEGF/TKI toxicities, he said.
 

What Treatments Are Recommended for Metastatic Clear Cell Renal Cell Carcinoma Now?

Clear cell renal cell carcinoma (ccRCC) is the most prevalent histological subtype of kidney cancer, accounting for 70%-75% of cases, and these patients are prone to metastasis, recurrence, and resistance to radiotherapy and chemotherapy, according to authors of a recent review published in Frontiers in Oncology.

Dr. Serzan shared his preferred protocol for treatment-naive metastatic ccRCC patients, based on the NCCN guidelines for Kidney Cancer (Version: 3.2024) that had been updated in 2024.

For those with sarcomatoid features, he favors the use of nivolumab/ipilimumab combination, while those without sarcomatoid features, if highly symptomatic, may be treated with any of several combinations: nivolumab/ipilimumab, axitinib/pembrolizumab, cabozantinib/nivolumab, or lenvatinib/pembrolizumab.

For asymptomatic patients without sarcomatoid features, treatment depends on eligibility for immune checkpoint inhibitors or ipilimumab, Dr. Serzan said. His first choice for those eligible is nivolumab/ipilimumab; those not eligible for ipilimumab could receive nivolumab, pembrolizumab, axitinib/pembrolizumab, cabozantinib/nivolumab, or lenvatinib/pembrolizumab.

For patients not eligible for ICIs because of uncontrolled autoimmune disease, or high-dose glucocorticoids, Dr. Serzan recommended treatment with cabozantinib, lenvatinib/everolimus, pazopanib, or sunitinib.
 

What are Some Takeaway Points About Immunotherapy and Renal Cell Carcinoma?

“Immunotherapy has revolutionized treatment for renal cell carcinoma, with significant increases in overall survival, and a small but consistent cure fraction that was unimaginable 10 years ago,” Eric Jonasch, MD, of The University of Texas MD Anderson Cancer Center and vice-chair of the NCCN Guidelines Panel for Kidney Cancer, said in an interview.

However, challenges to implementing new treatments in clinical practice are ongoing, he said. The major challenges facing clinicians, patients, and their families include the cost of therapy, logistics of treatment administration, and managing toxicities, Dr. Jonasch said.  

Patient selection is key to optimize outcomes with immunotherapy, and shared decision-making is essential to ensure that choice of therapy matches patient expectations and needs — and to maintain clear and open channels of communication while patients are on therapy, Dr. Jonasch said. “In my clinic, we empower patients to take treatment breaks to manage side effects, thereby optimizing quality of life while maintaining treatment efficacy,” he said.

Although significant progress has been made in managing renal cell carcinoma, more research is needed to increase the proportion of patients cured, said Dr. Jonasch. “A clearer understanding of the determinants of response and resistance, which will be driven by information rich clinical trials, will help move us in that direction,” he said.

Dr. Serzan had no financial conflicts to disclose. Dr. Jonasch disclosed research support from AbbVie, Arrowhead, Aveo, BMS, Corvus, Merck, NiKang, ProfoundBio, and Telix, as well as honoraria from Aveo, Eisai, Exelixis, GlaxoSmithKline, Ipsen, Merck, Novartis, NiKang, and Takeda.

The latest research supports immune checkpoint inhibitor therapy for clear cell and non–clear cell renal cell carcinoma, but patient selection is key to optimize outcomes, according to a medical oncologist from the Dana-Farber Cancer Institute, Boston.

Michael Serzan, MD, who works in the Lank Center for Genitourinary Oncology at the institute, stated this at the 2024 National Comprehensive Cancer Network Annual Conference, during a presentation.

A systematic review and meta-analysis published in 2022 in European Urology Open Science summarized six randomized controlled trials with a total of 5121 adult patients. In the review, the researchers found that immune checkpoint inhibitors plus vascular endothelial growth factor tyrosine kinase inhibitors (VEGF TKI) were associated with consistent improvements across all risk groups for metastatic renal cell carcinoma.

Additional newer research supports the use of immunotherapy combinations or other immunotherapy plus tyrosine kinase inhibitors as first-line or adjuvant treatments for renal cell carcinoma, Dr. Serzan said during an interview. However, more genomic and histology-directed therapies are needed, he noted.
 

Tips for Evaluating Risk When Treating Renal Cell Carcinoma?

For patients with localized clear cell renal cell carcinoma who have undergone partial or radical nephrectomy, there are several models that estimate the risk of recurrence based on pathologic tumor stage, grade, histology, invasion, and the extent of necrosis, Dr. Serzan said. These models can help guide selection of patients who may be at high risk of recurrence and, therefore, may benefit from adjuvant therapy.

For patients with metastatic clear cell renal cell carcinoma, the IMDC and MSKCC prognostic models stratify patients to favorable, intermediate, and poor risk groups based on clinical and lab factors. The IMDC risk stratification model is used as a prognostic model to stratify patients diagnosed with metastatic kidney cancer, Dr. Serzan said.
 

What Research Supports Treatments for Clear Cell and Non–Clear Cell Renal Cell Carcinoma?

The US Food and Drug Administration (FDA) approved pembrolizumab in 2021 for the adjuvant treatment of renal cell carcinoma (RCC) in patients with intermediate-risk or high-risk of recurrence after nephrectomy or after nephrectomy and resection of metastatic lesions.

Pembrolizumab is the first adjuvant therapy shown to significantly improve overall survival in these patients, Dr. Serzan said. In the KEYNOTE-564 study, published in 2024 in the Journal of Clinical Oncology, pembrolizumab demonstrated an improvement in disease free survival as well as overall survival when compared with placebo.

Several similar studies of adjuvant immune checkpoint inhibitors for renal cell carcinoma involving atezolizumab vs. placebo, nivolumab plus ipilimumab vs. placebo, and nivolumab vs. observation have not shown significant benefits in terms of disease-free survival, Dr. Serzan noted.

The current NCCN Clinical Practice Guidelines in Oncology for Kidney Cancer (Version: 3.2024), which were updated this year, support the use of adjuvant pembrolizumab for patients with stage II, III, or IV clear cell renal cell carcinoma after partial or radical nephrectomy, he said.

Looking ahead, biomarkers are needed to understand the risk of recurrence, and which patients benefit from adjuvant pembrolizumab, Dr. Serzan added.
 

Where Do VEGF-TKIs Fit In?

VEGF is a treatment target for renal cancer, and angiogenesis inhibition with VEGF TKIs continues to be a subject for study, Dr. Serzan said. In the CABOSUN study, published in the Journal of Clinical Oncology in 2017, patients were randomized to cabozantinib or sunitinib. Progression-free survival was significantly greater in the cabozantinib group, but overall survival was similar between the groups.

In another randomized trial, the CheckMate 214 study, patients received either sunitinib or a combination of nivolumab plus ipilimumab in four doses given every 3 weeks, followed by nivolumab alone every 2 weeks, and these patients were stratified by risk, Dr. Serzan noted.

The median progression-free survival was 12.4 months in the combination group vs. 8.5 months in the sunitinib group for patients at intermediate or poor risk of recurrence. The median progression-free survival was significantly greater in sunitinib patients with favorable risk vs. combination patients with favorable risk (28.9 months vs. 12.4 months).

Overall survival was higher for all patients with combination therapy vs. sunitinib regardless of risk stratification.

Dr. Serzan reviewed the pros of VEGF/PD1 (programmed death-ligand 1) combinations as including a high response rate (generally 52%-72%) and a low rate of primary progressive disease (5%-12%), as well as favorable progression-free and overall survival and low rates of immune-related adverse events.

However, cons of this treatment include lack of data on treatment-free survival as well as the decrease in progression-free survival and overall survival hazard ratios over time and potential chronic VEGF/TKI toxicities, he said.
 

What Treatments Are Recommended for Metastatic Clear Cell Renal Cell Carcinoma Now?

Clear cell renal cell carcinoma (ccRCC) is the most prevalent histological subtype of kidney cancer, accounting for 70%-75% of cases, and these patients are prone to metastasis, recurrence, and resistance to radiotherapy and chemotherapy, according to authors of a recent review published in Frontiers in Oncology.

Dr. Serzan shared his preferred protocol for treatment-naive metastatic ccRCC patients, based on the NCCN guidelines for Kidney Cancer (Version: 3.2024) that had been updated in 2024.

For those with sarcomatoid features, he favors the use of nivolumab/ipilimumab combination, while those without sarcomatoid features, if highly symptomatic, may be treated with any of several combinations: nivolumab/ipilimumab, axitinib/pembrolizumab, cabozantinib/nivolumab, or lenvatinib/pembrolizumab.

For asymptomatic patients without sarcomatoid features, treatment depends on eligibility for immune checkpoint inhibitors or ipilimumab, Dr. Serzan said. His first choice for those eligible is nivolumab/ipilimumab; those not eligible for ipilimumab could receive nivolumab, pembrolizumab, axitinib/pembrolizumab, cabozantinib/nivolumab, or lenvatinib/pembrolizumab.

For patients not eligible for ICIs because of uncontrolled autoimmune disease, or high-dose glucocorticoids, Dr. Serzan recommended treatment with cabozantinib, lenvatinib/everolimus, pazopanib, or sunitinib.
 

What are Some Takeaway Points About Immunotherapy and Renal Cell Carcinoma?

“Immunotherapy has revolutionized treatment for renal cell carcinoma, with significant increases in overall survival, and a small but consistent cure fraction that was unimaginable 10 years ago,” Eric Jonasch, MD, of The University of Texas MD Anderson Cancer Center and vice-chair of the NCCN Guidelines Panel for Kidney Cancer, said in an interview.

However, challenges to implementing new treatments in clinical practice are ongoing, he said. The major challenges facing clinicians, patients, and their families include the cost of therapy, logistics of treatment administration, and managing toxicities, Dr. Jonasch said.  

Patient selection is key to optimize outcomes with immunotherapy, and shared decision-making is essential to ensure that choice of therapy matches patient expectations and needs — and to maintain clear and open channels of communication while patients are on therapy, Dr. Jonasch said. “In my clinic, we empower patients to take treatment breaks to manage side effects, thereby optimizing quality of life while maintaining treatment efficacy,” he said.

Although significant progress has been made in managing renal cell carcinoma, more research is needed to increase the proportion of patients cured, said Dr. Jonasch. “A clearer understanding of the determinants of response and resistance, which will be driven by information rich clinical trials, will help move us in that direction,” he said.

Dr. Serzan had no financial conflicts to disclose. Dr. Jonasch disclosed research support from AbbVie, Arrowhead, Aveo, BMS, Corvus, Merck, NiKang, ProfoundBio, and Telix, as well as honoraria from Aveo, Eisai, Exelixis, GlaxoSmithKline, Ipsen, Merck, Novartis, NiKang, and Takeda.

Gut microbiota signatures associated with KRAS mutations in patients with colorectal cancer (CRC) have been identified by researchers.

Their findings suggest that the gut microbes may serve as noninvasive biomarkers to help identify subtypes of CRC and guide personalized treatment recommendations.

“Our new work contributes to the growing body of evidence highlighting the significance of microbiota-driven mechanisms in cancer pathogenesis,” lead investigator Weizhong Tang, MD, with Guangxi Medical University Cancer Hospital in Nanning, China, said in a statement. 

The research was recently published online in Microbiology Spectrum. 

The onset and growth of CRC has been linked both to imbalances in the gut microbiome and to mutations in the KRAS gene — about 40% of people with CRC have a KRAS mutation. Yet, the interplay between gut dysbiosis and KRAS mutations in CRC remains unclear. 

To investigate further, Dr. Tang and colleagues used 16s rRNA sequencing to analyze stool samples from 94 patients with CRC, including 24 with KRAS-mutated CRC and 70 with KRAS wild-type (nonmutated) CRC. 

The researchers identified 26 distinct types of gut microbiota with statistically significant differences in abundance between the KRAS mutant and KRAS wild-type CRC patients.

At the genus level, Fusobacterium, Clostridium, and Shewanella were all abundant in the KRAS mutant group. 

Fusobacterium is a Gram-negative microbe found in the gastrointestinal tract and the oral cavity. Recent studies have established a strong link between Fusobacterium and CRC development. Other work found elevated levels of Fusobacterium nucleatum were not only closely associated with KRAS mutation but also correlated with chemoresistance in CRC.

Clostridium produces metabolites in the large intestine, which are known to cause DNA damage and trigger inflammatory responses, thereby increasing the risk of CRC development. 

Similarly, Shewanella has been proven to be a contributor to CRC development.

The researchers say it’s “plausible” to consider all three as potential noninvasive biomarkers for identifying KRAS mutation in CRC patients.

In contrast, Bifidobacterium and Akkermansia were abundant in the KRAS wild-type group. 

Bifidobacterium is a probiotic with antitumor activity and Akkermansia is a Gram-negative anaerobic bacterium abundant in the gut and currently recognized as a potential probiotic. 

The researchers speculated that CRC patients may have a reduced likelihood of developing KRAS mutation in the presence of Bifidobacterium and Akkermansia.

Analyses of biological pathways of gut microbiota associated with KRAS mutation status in CRC revealed a significantly higher abundance of the isoflavonoid biosynthesis pathway in the KRAS wild-type group compared with the KRAS mutant group.

“In comparison to KRAS mutant CRC, it is postulated that KRAS wild-type CRC may be less aggressive due to the upregulation of the isoflavonoid biosynthesis pathway, which may inhibit CRC development and progression,” the authors wrote.

Promising Predictive Model

Dr. Tang and colleagues also developed a machine learning model to predict KRAS mutation status in CRC patients based on the gut microbiota signature in KRAS mutant CRC. 

The initial results underscore the model’s predictive efficacy and suggest that it has “considerable potential for clinical application, offering a novel dimension in the prediction of KRAS mutation status among CRC patients in a clinical setting,” the authors wrote. 

They caution that the model requires data from a larger cohort to improve its efficacy, and they plan to do larger studies to validate the findings. 

The study had no commercial funding. The authors declared no relevant conflicts of interest. 

A version of this article appeared on Medscape.com.

Gut microbiota signatures associated with KRAS mutations in patients with colorectal cancer (CRC) have been identified by researchers.

Their findings suggest that the gut microbes may serve as noninvasive biomarkers to help identify subtypes of CRC and guide personalized treatment recommendations.

“Our new work contributes to the growing body of evidence highlighting the significance of microbiota-driven mechanisms in cancer pathogenesis,” lead investigator Weizhong Tang, MD, with Guangxi Medical University Cancer Hospital in Nanning, China, said in a statement. 

The research was recently published online in Microbiology Spectrum. 

The onset and growth of CRC has been linked both to imbalances in the gut microbiome and to mutations in the KRAS gene — about 40% of people with CRC have a KRAS mutation. Yet, the interplay between gut dysbiosis and KRAS mutations in CRC remains unclear. 

To investigate further, Dr. Tang and colleagues used 16s rRNA sequencing to analyze stool samples from 94 patients with CRC, including 24 with KRAS-mutated CRC and 70 with KRAS wild-type (nonmutated) CRC. 

The researchers identified 26 distinct types of gut microbiota with statistically significant differences in abundance between the KRAS mutant and KRAS wild-type CRC patients.

At the genus level, Fusobacterium, Clostridium, and Shewanella were all abundant in the KRAS mutant group. 

Fusobacterium is a Gram-negative microbe found in the gastrointestinal tract and the oral cavity. Recent studies have established a strong link between Fusobacterium and CRC development. Other work found elevated levels of Fusobacterium nucleatum were not only closely associated with KRAS mutation but also correlated with chemoresistance in CRC.

Clostridium produces metabolites in the large intestine, which are known to cause DNA damage and trigger inflammatory responses, thereby increasing the risk of CRC development. 

Similarly, Shewanella has been proven to be a contributor to CRC development.

The researchers say it’s “plausible” to consider all three as potential noninvasive biomarkers for identifying KRAS mutation in CRC patients.

In contrast, Bifidobacterium and Akkermansia were abundant in the KRAS wild-type group. 

Bifidobacterium is a probiotic with antitumor activity and Akkermansia is a Gram-negative anaerobic bacterium abundant in the gut and currently recognized as a potential probiotic. 

The researchers speculated that CRC patients may have a reduced likelihood of developing KRAS mutation in the presence of Bifidobacterium and Akkermansia.

Analyses of biological pathways of gut microbiota associated with KRAS mutation status in CRC revealed a significantly higher abundance of the isoflavonoid biosynthesis pathway in the KRAS wild-type group compared with the KRAS mutant group.

“In comparison to KRAS mutant CRC, it is postulated that KRAS wild-type CRC may be less aggressive due to the upregulation of the isoflavonoid biosynthesis pathway, which may inhibit CRC development and progression,” the authors wrote.

Promising Predictive Model

Dr. Tang and colleagues also developed a machine learning model to predict KRAS mutation status in CRC patients based on the gut microbiota signature in KRAS mutant CRC. 

The initial results underscore the model’s predictive efficacy and suggest that it has “considerable potential for clinical application, offering a novel dimension in the prediction of KRAS mutation status among CRC patients in a clinical setting,” the authors wrote. 

They caution that the model requires data from a larger cohort to improve its efficacy, and they plan to do larger studies to validate the findings. 

The study had no commercial funding. The authors declared no relevant conflicts of interest. 

A version of this article appeared on Medscape.com.

Gut microbiota signatures associated with KRAS mutations in patients with colorectal cancer (CRC) have been identified by researchers.

Their findings suggest that the gut microbes may serve as noninvasive biomarkers to help identify subtypes of CRC and guide personalized treatment recommendations.

“Our new work contributes to the growing body of evidence highlighting the significance of microbiota-driven mechanisms in cancer pathogenesis,” lead investigator Weizhong Tang, MD, with Guangxi Medical University Cancer Hospital in Nanning, China, said in a statement. 

The research was recently published online in Microbiology Spectrum. 

The onset and growth of CRC has been linked both to imbalances in the gut microbiome and to mutations in the KRAS gene — about 40% of people with CRC have a KRAS mutation. Yet, the interplay between gut dysbiosis and KRAS mutations in CRC remains unclear. 

To investigate further, Dr. Tang and colleagues used 16s rRNA sequencing to analyze stool samples from 94 patients with CRC, including 24 with KRAS-mutated CRC and 70 with KRAS wild-type (nonmutated) CRC. 

The researchers identified 26 distinct types of gut microbiota with statistically significant differences in abundance between the KRAS mutant and KRAS wild-type CRC patients.

At the genus level, Fusobacterium, Clostridium, and Shewanella were all abundant in the KRAS mutant group. 

Fusobacterium is a Gram-negative microbe found in the gastrointestinal tract and the oral cavity. Recent studies have established a strong link between Fusobacterium and CRC development. Other work found elevated levels of Fusobacterium nucleatum were not only closely associated with KRAS mutation but also correlated with chemoresistance in CRC.

Clostridium produces metabolites in the large intestine, which are known to cause DNA damage and trigger inflammatory responses, thereby increasing the risk of CRC development. 

Similarly, Shewanella has been proven to be a contributor to CRC development.

The researchers say it’s “plausible” to consider all three as potential noninvasive biomarkers for identifying KRAS mutation in CRC patients.

In contrast, Bifidobacterium and Akkermansia were abundant in the KRAS wild-type group. 

Bifidobacterium is a probiotic with antitumor activity and Akkermansia is a Gram-negative anaerobic bacterium abundant in the gut and currently recognized as a potential probiotic. 

The researchers speculated that CRC patients may have a reduced likelihood of developing KRAS mutation in the presence of Bifidobacterium and Akkermansia.

Analyses of biological pathways of gut microbiota associated with KRAS mutation status in CRC revealed a significantly higher abundance of the isoflavonoid biosynthesis pathway in the KRAS wild-type group compared with the KRAS mutant group.

“In comparison to KRAS mutant CRC, it is postulated that KRAS wild-type CRC may be less aggressive due to the upregulation of the isoflavonoid biosynthesis pathway, which may inhibit CRC development and progression,” the authors wrote.

Promising Predictive Model

Dr. Tang and colleagues also developed a machine learning model to predict KRAS mutation status in CRC patients based on the gut microbiota signature in KRAS mutant CRC. 

The initial results underscore the model’s predictive efficacy and suggest that it has “considerable potential for clinical application, offering a novel dimension in the prediction of KRAS mutation status among CRC patients in a clinical setting,” the authors wrote. 

They caution that the model requires data from a larger cohort to improve its efficacy, and they plan to do larger studies to validate the findings. 

The study had no commercial funding. The authors declared no relevant conflicts of interest. 

A version of this article appeared on Medscape.com.

TOPLINE:

An analysis of molecular-targeted cancer drug therapies recently approved in the United States found that fewer than one-third demonstrated substantial clinical benefits at the time of approval.

METHODOLOGY:

• The strength and quality of evidence supporting genome-targeted cancer drug approvals vary. A big reason is the growing number of cancer drug approvals based on surrogate endpoints, such as disease-free and progression-free survival, instead of clinical endpoints, such as overall survival or quality of life. The US Food and Drug Administration (FDA) has also approved genome-targeted cancer drugs based on phase 1 or single-arm trials.
• Given these less rigorous considerations for approval, “the validity and value of the targets and surrogate measures underlying FDA genome-targeted cancer drug approvals are uncertain,” the researchers explained.
• In the current analysis, researchers assessed the validity of the molecular targets as well as the clinical benefits of genome-targeted cancer drugs approved in the United States from 2015 to 2022 based on results from pivotal trials.
• The researchers evaluated the strength of evidence supporting molecular targetability using the European Society for Medical Oncology (ESMO) Scale for Clinical Actionability of Molecular Targets (ESCAT) and the clinical benefit using the ESMO–Magnitude of Clinical Benefit Scale (ESMO-MCBS).
• The authors defined a substantial clinical benefit as an A or B grade for curative intent and a 4 or 5 for noncurative intent. High-benefit genomic-based cancer treatments were defined as those associated with a substantial clinical benefit (ESMO-MCBS) and that qualified as ESCAT category level I-A (a clinical benefit based on prospective randomized data) or I-B (prospective nonrandomized data).

TAKEAWAY:

• The analyses focused on 50 molecular-targeted cancer drugs covering 84 indications. Of which, 45 indications (54%) were approved based on phase 1 or 2 pivotal trials, 45 (54%) were supported by single-arm pivotal trials and the remaining 39 (46%) by randomized trial, and 48 (57%) were approved based on subgroup analyses.
• Among the 84 indications, more than half (55%) of the pivotal trials supporting approval used overall response rate as a primary endpoint, 31% used progression-free survival, and 6% used disease-free survival. Only seven indications (8%) were supported by pivotal trials demonstrating an improvement in overall survival.
• Among the 84 trials, 24 (29%) met the ESMO-MCBS threshold for substantial clinical benefit.
• Overall, when combining all ratings, only 24 of the 84 indications (29%) were considered high-benefit genomic-based cancer treatments.

IN PRACTICE:

“We applied the ESMO-MCBS and ESCAT value frameworks to identify therapies and molecular targets providing high clinical value that should be widely available to patients” and “found that drug indications supported by these characteristics represent a minority of cancer drug approvals in recent years,” the authors said. Using these value frameworks could help payers, governments, and individual patients “prioritize the availability of high-value molecular-targeted therapies.”

SOURCE:

The study, with first author Ariadna Tibau, MD, PhD, Brigham and Women’s Hospital and Harvard Medical School, Boston, was published online in JAMA Oncology.

LIMITATIONS:

The study evaluated only trials that supported regulatory approval and did not include outcomes of postapproval clinical studies, which could lead to changes in ESMO-MCBS grades and ESCAT levels of evidence over time.

DISCLOSURES:

The study was funded by the Kaiser Permanente Institute for Health Policy, Arnold Ventures, and the Commonwealth Fund. The authors had no relevant disclosures.

A version of this article appeared on Medscape.com.

TOPLINE:

An analysis of molecular-targeted cancer drug therapies recently approved in the United States found that fewer than one-third demonstrated substantial clinical benefits at the time of approval.

METHODOLOGY:

• The strength and quality of evidence supporting genome-targeted cancer drug approvals vary. A big reason is the growing number of cancer drug approvals based on surrogate endpoints, such as disease-free and progression-free survival, instead of clinical endpoints, such as overall survival or quality of life. The US Food and Drug Administration (FDA) has also approved genome-targeted cancer drugs based on phase 1 or single-arm trials.
• Given these less rigorous considerations for approval, “the validity and value of the targets and surrogate measures underlying FDA genome-targeted cancer drug approvals are uncertain,” the researchers explained.
• In the current analysis, researchers assessed the validity of the molecular targets as well as the clinical benefits of genome-targeted cancer drugs approved in the United States from 2015 to 2022 based on results from pivotal trials.
• The researchers evaluated the strength of evidence supporting molecular targetability using the European Society for Medical Oncology (ESMO) Scale for Clinical Actionability of Molecular Targets (ESCAT) and the clinical benefit using the ESMO–Magnitude of Clinical Benefit Scale (ESMO-MCBS).
• The authors defined a substantial clinical benefit as an A or B grade for curative intent and a 4 or 5 for noncurative intent. High-benefit genomic-based cancer treatments were defined as those associated with a substantial clinical benefit (ESMO-MCBS) and that qualified as ESCAT category level I-A (a clinical benefit based on prospective randomized data) or I-B (prospective nonrandomized data).

TAKEAWAY:

• The analyses focused on 50 molecular-targeted cancer drugs covering 84 indications. Of which, 45 indications (54%) were approved based on phase 1 or 2 pivotal trials, 45 (54%) were supported by single-arm pivotal trials and the remaining 39 (46%) by randomized trial, and 48 (57%) were approved based on subgroup analyses.
• Among the 84 indications, more than half (55%) of the pivotal trials supporting approval used overall response rate as a primary endpoint, 31% used progression-free survival, and 6% used disease-free survival. Only seven indications (8%) were supported by pivotal trials demonstrating an improvement in overall survival.
• Among the 84 trials, 24 (29%) met the ESMO-MCBS threshold for substantial clinical benefit.
• Overall, when combining all ratings, only 24 of the 84 indications (29%) were considered high-benefit genomic-based cancer treatments.

IN PRACTICE:

“We applied the ESMO-MCBS and ESCAT value frameworks to identify therapies and molecular targets providing high clinical value that should be widely available to patients” and “found that drug indications supported by these characteristics represent a minority of cancer drug approvals in recent years,” the authors said. Using these value frameworks could help payers, governments, and individual patients “prioritize the availability of high-value molecular-targeted therapies.”

SOURCE:

The study, with first author Ariadna Tibau, MD, PhD, Brigham and Women’s Hospital and Harvard Medical School, Boston, was published online in JAMA Oncology.

LIMITATIONS:

The study evaluated only trials that supported regulatory approval and did not include outcomes of postapproval clinical studies, which could lead to changes in ESMO-MCBS grades and ESCAT levels of evidence over time.

DISCLOSURES:

The study was funded by the Kaiser Permanente Institute for Health Policy, Arnold Ventures, and the Commonwealth Fund. The authors had no relevant disclosures.

A version of this article appeared on Medscape.com.

TOPLINE:

An analysis of molecular-targeted cancer drug therapies recently approved in the United States found that fewer than one-third demonstrated substantial clinical benefits at the time of approval.

METHODOLOGY:

• The strength and quality of evidence supporting genome-targeted cancer drug approvals vary. A big reason is the growing number of cancer drug approvals based on surrogate endpoints, such as disease-free and progression-free survival, instead of clinical endpoints, such as overall survival or quality of life. The US Food and Drug Administration (FDA) has also approved genome-targeted cancer drugs based on phase 1 or single-arm trials.
• Given these less rigorous considerations for approval, “the validity and value of the targets and surrogate measures underlying FDA genome-targeted cancer drug approvals are uncertain,” the researchers explained.
• In the current analysis, researchers assessed the validity of the molecular targets as well as the clinical benefits of genome-targeted cancer drugs approved in the United States from 2015 to 2022 based on results from pivotal trials.
• The researchers evaluated the strength of evidence supporting molecular targetability using the European Society for Medical Oncology (ESMO) Scale for Clinical Actionability of Molecular Targets (ESCAT) and the clinical benefit using the ESMO–Magnitude of Clinical Benefit Scale (ESMO-MCBS).
• The authors defined a substantial clinical benefit as an A or B grade for curative intent and a 4 or 5 for noncurative intent. High-benefit genomic-based cancer treatments were defined as those associated with a substantial clinical benefit (ESMO-MCBS) and that qualified as ESCAT category level I-A (a clinical benefit based on prospective randomized data) or I-B (prospective nonrandomized data).

TAKEAWAY:

• The analyses focused on 50 molecular-targeted cancer drugs covering 84 indications. Of which, 45 indications (54%) were approved based on phase 1 or 2 pivotal trials, 45 (54%) were supported by single-arm pivotal trials and the remaining 39 (46%) by randomized trial, and 48 (57%) were approved based on subgroup analyses.
• Among the 84 indications, more than half (55%) of the pivotal trials supporting approval used overall response rate as a primary endpoint, 31% used progression-free survival, and 6% used disease-free survival. Only seven indications (8%) were supported by pivotal trials demonstrating an improvement in overall survival.
• Among the 84 trials, 24 (29%) met the ESMO-MCBS threshold for substantial clinical benefit.
• Overall, when combining all ratings, only 24 of the 84 indications (29%) were considered high-benefit genomic-based cancer treatments.

IN PRACTICE:

“We applied the ESMO-MCBS and ESCAT value frameworks to identify therapies and molecular targets providing high clinical value that should be widely available to patients” and “found that drug indications supported by these characteristics represent a minority of cancer drug approvals in recent years,” the authors said. Using these value frameworks could help payers, governments, and individual patients “prioritize the availability of high-value molecular-targeted therapies.”

SOURCE:

The study, with first author Ariadna Tibau, MD, PhD, Brigham and Women’s Hospital and Harvard Medical School, Boston, was published online in JAMA Oncology.

LIMITATIONS:

The study evaluated only trials that supported regulatory approval and did not include outcomes of postapproval clinical studies, which could lead to changes in ESMO-MCBS grades and ESCAT levels of evidence over time.

DISCLOSURES:

The study was funded by the Kaiser Permanente Institute for Health Policy, Arnold Ventures, and the Commonwealth Fund. The authors had no relevant disclosures.

A version of this article appeared on Medscape.com.

SAN DIEGO — A new cell-free DNA (cfDNA)-based blood test shows promising performance in detecting colorectal cancer and advanced precancerous lesions, say the authors of new research.

Rachel B. Issaka, MD, MAS, of the Fred Hutchinson Cancer Center, Seattle, presented the clinical data, which was published in The New England Journal of Medicine, at the American Association for Cancer Research annual meeting.

Issaka_Rachel_WASH_web.jpg

The authors of the study evaluated the performance of a cfDNA blood-based test in a population eligible for colorectal cancer screening. The researchers found that the test had high sensitivity for the detection of colorectal cancer and high specificity for advanced precancerous lesions.

This novel blood test could improve screening adherence and, ultimately, reduce colorectal cancer-related mortality, Dr. Issaka said during her presentation.

“This test has the potential to help us reach the 80% screening target in colorectal cancer. However, this will depend on many factors, including access, implementation, follow-up colonoscopy, and characteristics of the test,” Dr. Issaka said in an interview.

She added that, when approved for broader use, anyone who wants to use this blood test for colorectal cancer screening should have a frank conversation with their healthcare provider.

“Considering the person’s age, medical history, family history, and any potential symptoms, and how the test performs will dictate if it’s the right test for that person versus another screening strategy,” Dr. Issaka explained.
 

The Blood Test Detects Colorectal Cancer With High Accuracy

The investigators of the observational ECLIPSE trial evaluated the performance of the cfDNA-based blood test in 7861 individuals who were eligible for colorectal cancer screening. The study population included people from more than 200 rural and urban sites across 34 states, including community hospitals, private practices, gastroenterology clinics, and academic centers. “The study enrolled a diverse cohort that is reflective of the demographics of the intended use population in the US,” Dr. Issaka said during her talk.

The co-primary outcomes of the study were the test’s sensitivity for detecting colorectal cancer and its specificity for identifying advanced neoplasia.

In her presentation, Dr. Issaka highlighted that the test had 83.1% (95% confidence interval [CI], 72.2%-90.3%) sensitivity for the detection of colorectal cancer, meaning that it was able to correctly identify most participants with the disease. The test’s sensitivity was even higher (87.5%; 95% CI, 75.3%-94.1%) for stage I, II, or III colorectal cancer. “These are the stages at which early intervention can have the greatest impact on patient prognosis,” Dr. Issaka said.

Moreover, the blood test showed 89.6% (95% CI, 88.8%-90.3%) specificity for advanced neoplasia, including colorectal cancer and advanced precancerous lesions. The specificity of the test for negative colonoscopy results (no colorectal cancer, advanced precancerous lesions, or nonadvanced precancerous lesions) was 89.9% (95% CI, 89.0%-90.7%).

Dr. Issaka highlighted that this cfDNA assay is the first blood-based test with performance comparable to current guideline-recommended noninvasive options for CRC.
 

The Blood Test Shows Limited Ability To Detect Advanced Precancerous Lesions

During her presentation, Dr. Issaka acknowledged that the cfDNA-based blood test had a lower sensitivity (13.2%; 95% CI, 11.3%-15.3%) for the detection of advanced precancerous lesions, suggesting that it may be more effective at identifying established cancers than early-stage precancerous changes. Low sensitivity was also observed for high-grade dysplasia (22.6%; 95% CI, 11.4%-39.8%). However, she emphasized that the test could still play a valuable role in a comprehensive screening approach, potentially serving as a first-line tool to identify individuals who would then undergo follow-up colonoscopy.

“Although blood-based tests perform well at finding cancers, they do not do so well at finding precancerous polyps. This is relevant because colorectal cancer is one of the few cancers that we can prevent by finding and removing precancerous polyps,” Folasade P. May, MD, PhD, MPhil, said in an interview.

“Users must also understand that if the test result is abnormal, a colonoscopy is required to look for cancers and polyps that might have caused the abnormal result,” added Dr. May, associate professor at UCLA. She was not involved in the study.
 

Clinical Implications and Future Steps

According to the study published in the NEJM, colorectal cancer is the third most commonly diagnosed cancer in the United States, and early detection is crucial for effective treatment. However, over a third of eligible individuals are not up to date with recommended screening.

During her talk, Dr. Issaka noted that colonoscopy is the most commonly used screening method for colorectal cancer. What contributes to the low adherence to getting a colonoscopy among the eligible population is that some find it inconvenient, and the test is invasive, she added.

According to Dr. May, the key advantage of cfDNA-based screening is that many people will find it easier to complete a blood test than the currently available screening tests.

“This option may allow us to screen individuals that we have previously struggled to convince to get screened for colorectal cancer,” she said.

In an interview, Dr. Issaka acknowledged that the potential public health impact of any noninvasive screening test depends on how many people with abnormal results complete a follow-up colonoscopy. “This is an important quality metric to track,” she said.

In an interview, Dr. Issaka emphasized that comparing this cfDNA blood test with emerging blood tests and other noninvasive screening strategies will empower patients and clinicians to select the right test at the right time for the right patient.

She added that the study was conducted in an average-risk screening population and that further research is needed to evaluate the test’s performance in higher-risk groups and to assess its real-world impact on screening adherence and colorectal cancer-related outcomes.

Commenting on potential challenges with implementing this cfDNA blood test in clinical practice, Dr. May said, “As we consider incorporating blood-based tests into clinical practice, some challenges include cost, equitable access to tests and follow-up, performance in young adults who are newly eligible for screening, and follow-up after abnormal results.”

She added that, if there is uptake of these tests, it will be important to track how that impacts colorectal cancer screening rates, stage at diagnosis, and whether there is stage migration, incidence, and mortality.

“At this time, I feel that these tests are appropriate for individuals who will not or cannot participate in one of the currently recommended screening tests. These include colonoscopy and stool-based tests, like FIT and FIT-DNA,” Dr. May concluded.

Dr. Issaka reported financial relationships with the National Institutes of Health/National Cancer Institute, American College of Gastroenterology, and Guardant Health Inc. Dr. May reported financial relationships with Takeda, Medtronic, Johnson & Johnson, Saint Supply, Exact Sciences, Freenome, Geneoscopy, Guardant Health, InterVenn, Natura, National Institutes of Health/National Cancer Institute, Veterans Affairs HSR&D, Broad Institute, Stand up to Cancer, and NRG Oncology.

SAN DIEGO — A new cell-free DNA (cfDNA)-based blood test shows promising performance in detecting colorectal cancer and advanced precancerous lesions, say the authors of new research.

Rachel B. Issaka, MD, MAS, of the Fred Hutchinson Cancer Center, Seattle, presented the clinical data, which was published in The New England Journal of Medicine, at the American Association for Cancer Research annual meeting.

Issaka_Rachel_WASH_web.jpg

The authors of the study evaluated the performance of a cfDNA blood-based test in a population eligible for colorectal cancer screening. The researchers found that the test had high sensitivity for the detection of colorectal cancer and high specificity for advanced precancerous lesions.

This novel blood test could improve screening adherence and, ultimately, reduce colorectal cancer-related mortality, Dr. Issaka said during her presentation.

“This test has the potential to help us reach the 80% screening target in colorectal cancer. However, this will depend on many factors, including access, implementation, follow-up colonoscopy, and characteristics of the test,” Dr. Issaka said in an interview.

She added that, when approved for broader use, anyone who wants to use this blood test for colorectal cancer screening should have a frank conversation with their healthcare provider.

“Considering the person’s age, medical history, family history, and any potential symptoms, and how the test performs will dictate if it’s the right test for that person versus another screening strategy,” Dr. Issaka explained.
 

The Blood Test Detects Colorectal Cancer With High Accuracy

The investigators of the observational ECLIPSE trial evaluated the performance of the cfDNA-based blood test in 7861 individuals who were eligible for colorectal cancer screening. The study population included people from more than 200 rural and urban sites across 34 states, including community hospitals, private practices, gastroenterology clinics, and academic centers. “The study enrolled a diverse cohort that is reflective of the demographics of the intended use population in the US,” Dr. Issaka said during her talk.

The co-primary outcomes of the study were the test’s sensitivity for detecting colorectal cancer and its specificity for identifying advanced neoplasia.

In her presentation, Dr. Issaka highlighted that the test had 83.1% (95% confidence interval [CI], 72.2%-90.3%) sensitivity for the detection of colorectal cancer, meaning that it was able to correctly identify most participants with the disease. The test’s sensitivity was even higher (87.5%; 95% CI, 75.3%-94.1%) for stage I, II, or III colorectal cancer. “These are the stages at which early intervention can have the greatest impact on patient prognosis,” Dr. Issaka said.

Moreover, the blood test showed 89.6% (95% CI, 88.8%-90.3%) specificity for advanced neoplasia, including colorectal cancer and advanced precancerous lesions. The specificity of the test for negative colonoscopy results (no colorectal cancer, advanced precancerous lesions, or nonadvanced precancerous lesions) was 89.9% (95% CI, 89.0%-90.7%).

Dr. Issaka highlighted that this cfDNA assay is the first blood-based test with performance comparable to current guideline-recommended noninvasive options for CRC.
 

The Blood Test Shows Limited Ability To Detect Advanced Precancerous Lesions

During her presentation, Dr. Issaka acknowledged that the cfDNA-based blood test had a lower sensitivity (13.2%; 95% CI, 11.3%-15.3%) for the detection of advanced precancerous lesions, suggesting that it may be more effective at identifying established cancers than early-stage precancerous changes. Low sensitivity was also observed for high-grade dysplasia (22.6%; 95% CI, 11.4%-39.8%). However, she emphasized that the test could still play a valuable role in a comprehensive screening approach, potentially serving as a first-line tool to identify individuals who would then undergo follow-up colonoscopy.

“Although blood-based tests perform well at finding cancers, they do not do so well at finding precancerous polyps. This is relevant because colorectal cancer is one of the few cancers that we can prevent by finding and removing precancerous polyps,” Folasade P. May, MD, PhD, MPhil, said in an interview.

“Users must also understand that if the test result is abnormal, a colonoscopy is required to look for cancers and polyps that might have caused the abnormal result,” added Dr. May, associate professor at UCLA. She was not involved in the study.
 

Clinical Implications and Future Steps

According to the study published in the NEJM, colorectal cancer is the third most commonly diagnosed cancer in the United States, and early detection is crucial for effective treatment. However, over a third of eligible individuals are not up to date with recommended screening.

During her talk, Dr. Issaka noted that colonoscopy is the most commonly used screening method for colorectal cancer. What contributes to the low adherence to getting a colonoscopy among the eligible population is that some find it inconvenient, and the test is invasive, she added.

According to Dr. May, the key advantage of cfDNA-based screening is that many people will find it easier to complete a blood test than the currently available screening tests.

“This option may allow us to screen individuals that we have previously struggled to convince to get screened for colorectal cancer,” she said.

In an interview, Dr. Issaka acknowledged that the potential public health impact of any noninvasive screening test depends on how many people with abnormal results complete a follow-up colonoscopy. “This is an important quality metric to track,” she said.

In an interview, Dr. Issaka emphasized that comparing this cfDNA blood test with emerging blood tests and other noninvasive screening strategies will empower patients and clinicians to select the right test at the right time for the right patient.

She added that the study was conducted in an average-risk screening population and that further research is needed to evaluate the test’s performance in higher-risk groups and to assess its real-world impact on screening adherence and colorectal cancer-related outcomes.

Commenting on potential challenges with implementing this cfDNA blood test in clinical practice, Dr. May said, “As we consider incorporating blood-based tests into clinical practice, some challenges include cost, equitable access to tests and follow-up, performance in young adults who are newly eligible for screening, and follow-up after abnormal results.”

She added that, if there is uptake of these tests, it will be important to track how that impacts colorectal cancer screening rates, stage at diagnosis, and whether there is stage migration, incidence, and mortality.

“At this time, I feel that these tests are appropriate for individuals who will not or cannot participate in one of the currently recommended screening tests. These include colonoscopy and stool-based tests, like FIT and FIT-DNA,” Dr. May concluded.

Dr. Issaka reported financial relationships with the National Institutes of Health/National Cancer Institute, American College of Gastroenterology, and Guardant Health Inc. Dr. May reported financial relationships with Takeda, Medtronic, Johnson & Johnson, Saint Supply, Exact Sciences, Freenome, Geneoscopy, Guardant Health, InterVenn, Natura, National Institutes of Health/National Cancer Institute, Veterans Affairs HSR&D, Broad Institute, Stand up to Cancer, and NRG Oncology.

SAN DIEGO — A new cell-free DNA (cfDNA)-based blood test shows promising performance in detecting colorectal cancer and advanced precancerous lesions, say the authors of new research.

Rachel B. Issaka, MD, MAS, of the Fred Hutchinson Cancer Center, Seattle, presented the clinical data, which was published in The New England Journal of Medicine, at the American Association for Cancer Research annual meeting.

Issaka_Rachel_WASH_web.jpg

The authors of the study evaluated the performance of a cfDNA blood-based test in a population eligible for colorectal cancer screening. The researchers found that the test had high sensitivity for the detection of colorectal cancer and high specificity for advanced precancerous lesions.

This novel blood test could improve screening adherence and, ultimately, reduce colorectal cancer-related mortality, Dr. Issaka said during her presentation.

“This test has the potential to help us reach the 80% screening target in colorectal cancer. However, this will depend on many factors, including access, implementation, follow-up colonoscopy, and characteristics of the test,” Dr. Issaka said in an interview.

She added that, when approved for broader use, anyone who wants to use this blood test for colorectal cancer screening should have a frank conversation with their healthcare provider.

“Considering the person’s age, medical history, family history, and any potential symptoms, and how the test performs will dictate if it’s the right test for that person versus another screening strategy,” Dr. Issaka explained.
 

The Blood Test Detects Colorectal Cancer With High Accuracy

The investigators of the observational ECLIPSE trial evaluated the performance of the cfDNA-based blood test in 7861 individuals who were eligible for colorectal cancer screening. The study population included people from more than 200 rural and urban sites across 34 states, including community hospitals, private practices, gastroenterology clinics, and academic centers. “The study enrolled a diverse cohort that is reflective of the demographics of the intended use population in the US,” Dr. Issaka said during her talk.

The co-primary outcomes of the study were the test’s sensitivity for detecting colorectal cancer and its specificity for identifying advanced neoplasia.

In her presentation, Dr. Issaka highlighted that the test had 83.1% (95% confidence interval [CI], 72.2%-90.3%) sensitivity for the detection of colorectal cancer, meaning that it was able to correctly identify most participants with the disease. The test’s sensitivity was even higher (87.5%; 95% CI, 75.3%-94.1%) for stage I, II, or III colorectal cancer. “These are the stages at which early intervention can have the greatest impact on patient prognosis,” Dr. Issaka said.

Moreover, the blood test showed 89.6% (95% CI, 88.8%-90.3%) specificity for advanced neoplasia, including colorectal cancer and advanced precancerous lesions. The specificity of the test for negative colonoscopy results (no colorectal cancer, advanced precancerous lesions, or nonadvanced precancerous lesions) was 89.9% (95% CI, 89.0%-90.7%).

Dr. Issaka highlighted that this cfDNA assay is the first blood-based test with performance comparable to current guideline-recommended noninvasive options for CRC.
 

The Blood Test Shows Limited Ability To Detect Advanced Precancerous Lesions

During her presentation, Dr. Issaka acknowledged that the cfDNA-based blood test had a lower sensitivity (13.2%; 95% CI, 11.3%-15.3%) for the detection of advanced precancerous lesions, suggesting that it may be more effective at identifying established cancers than early-stage precancerous changes. Low sensitivity was also observed for high-grade dysplasia (22.6%; 95% CI, 11.4%-39.8%). However, she emphasized that the test could still play a valuable role in a comprehensive screening approach, potentially serving as a first-line tool to identify individuals who would then undergo follow-up colonoscopy.

“Although blood-based tests perform well at finding cancers, they do not do so well at finding precancerous polyps. This is relevant because colorectal cancer is one of the few cancers that we can prevent by finding and removing precancerous polyps,” Folasade P. May, MD, PhD, MPhil, said in an interview.

“Users must also understand that if the test result is abnormal, a colonoscopy is required to look for cancers and polyps that might have caused the abnormal result,” added Dr. May, associate professor at UCLA. She was not involved in the study.
 

Clinical Implications and Future Steps

According to the study published in the NEJM, colorectal cancer is the third most commonly diagnosed cancer in the United States, and early detection is crucial for effective treatment. However, over a third of eligible individuals are not up to date with recommended screening.

During her talk, Dr. Issaka noted that colonoscopy is the most commonly used screening method for colorectal cancer. What contributes to the low adherence to getting a colonoscopy among the eligible population is that some find it inconvenient, and the test is invasive, she added.

According to Dr. May, the key advantage of cfDNA-based screening is that many people will find it easier to complete a blood test than the currently available screening tests.

“This option may allow us to screen individuals that we have previously struggled to convince to get screened for colorectal cancer,” she said.

In an interview, Dr. Issaka acknowledged that the potential public health impact of any noninvasive screening test depends on how many people with abnormal results complete a follow-up colonoscopy. “This is an important quality metric to track,” she said.

In an interview, Dr. Issaka emphasized that comparing this cfDNA blood test with emerging blood tests and other noninvasive screening strategies will empower patients and clinicians to select the right test at the right time for the right patient.

She added that the study was conducted in an average-risk screening population and that further research is needed to evaluate the test’s performance in higher-risk groups and to assess its real-world impact on screening adherence and colorectal cancer-related outcomes.

Commenting on potential challenges with implementing this cfDNA blood test in clinical practice, Dr. May said, “As we consider incorporating blood-based tests into clinical practice, some challenges include cost, equitable access to tests and follow-up, performance in young adults who are newly eligible for screening, and follow-up after abnormal results.”

She added that, if there is uptake of these tests, it will be important to track how that impacts colorectal cancer screening rates, stage at diagnosis, and whether there is stage migration, incidence, and mortality.

“At this time, I feel that these tests are appropriate for individuals who will not or cannot participate in one of the currently recommended screening tests. These include colonoscopy and stool-based tests, like FIT and FIT-DNA,” Dr. May concluded.

Dr. Issaka reported financial relationships with the National Institutes of Health/National Cancer Institute, American College of Gastroenterology, and Guardant Health Inc. Dr. May reported financial relationships with Takeda, Medtronic, Johnson & Johnson, Saint Supply, Exact Sciences, Freenome, Geneoscopy, Guardant Health, InterVenn, Natura, National Institutes of Health/National Cancer Institute, Veterans Affairs HSR&D, Broad Institute, Stand up to Cancer, and NRG Oncology.

Early data suggested that several new multicancer early detection (MCED) tests in development show promise for identifying cancers that lack routine screening options.

Analyses presented during a session at the American Association for Cancer Research annual meeting, revealed that three new MCED tests — CanScan, MERCURY, and OncoSeek — could detect a range of cancers and recognize the tissue of origin with high accuracy. One — OncoSeek — could also provide an affordable cancer screening option for individuals living in lower-income countries.

The need for these noninvasive liquid biopsy tests that can accurately identify multiple cancer types with a single blood draw, especially cancers without routine screening strategies, is pressing. “We know that the current cancer standard of care screening will identify less than 50% of all cancers, while more than 50% of all cancer deaths occur in types of cancer with no recommended screening,” said co-moderator Marie E. Wood, MD, of the University of Colorado Anschutz Medical Campus, in Aurora, Colorado.

That being said, “the clinical utility of multicancer detection tests has not been established and we’re concerned about issues of overdiagnosis and overtreatment,” she noted.

The Early Data 

One new MCED test called CanScan, developed by Geneseeq Technology, uses plasma cell-free DNA fragment patterns to detect cancer signals as well as identify the tissue of origin across 13 cancer types.

Overall, the CanScan test covers cancer types that contribute to two thirds of new cancer cases and 74% of morality globally, said presenter Shanshan Yang, of Geneseeq Research Institute, in Nanjing, China.

However, only five of these cancer types have screening recommendations issued by the US Preventive Services Task Force (USPSTF), Dr. Yang added.

The interim data comes from an ongoing large-scale prospective study evaluating the MCED test in a cohort of asymptomatic individuals between ages 45 and 75 years with an average risk for cancer and no cancer-related symptoms on enrollment.

Patients at baseline had their blood collected for the CanScan test and subsequently received annual routine physical exams once a year for 3 consecutive years, with an additional 2 years of follow-up. 

The analysis included 3724 participants with analyzable samples at the data cutoff in September 2023. Among the 3724 participants, 29 had confirmed cancer diagnoses. Among these cases, 14 patients had their cancer confirmed through USPSTF recommended screening and 15 were detected through outside of standard USPSTF screening, such as a thyroid ultrasound, Dr. Yang explained.

Almost 90% of the cancers (26 of 29) were detected in the stage I or II, and eight (27.5%) were not one of the test’s 13 targeted cancer types.

The CanScan test had a sensitivity of 55.2%, identifying 16 of 29 of the patients with cancer, including 10 of 21 individuals with stage I (47.6%), and two of three with stage II (66.7%). 

The test had a high specificity of 97.9%, meaning out of 100 people screened, only two had false negative findings.

Among the 15 patients who had their cancer detected outside of USPSTF screening recommendations, eight (53.3%) were found using a CanScan test, including patients with liver and endometrial cancers.

Compared with a positive predictive value of (PPV) of 1.6% with screening or physical exam methods alone, the CanScan test had a PPV of 17.4%, Dr. Yang reported. 

“The MCED test holds significant potential for early cancer screening in asymptomatic populations,” Dr. Yang and colleagues concluded.

Another new MCED test called MERCURY, also developed by Geneseeq Technology and presented during the session, used a similar method to detect cancer signals and predict the tissue of origin across 13 cancer types.

The researchers initially validated the test using 3076 patients with cancer and 3477 healthy controls with a target specificity of 99%. In this group, researchers reported a sensitivity of 0.865 and a specificity of 0.989.

The team then performed an independent validation analysis with 1465 participants, 732 with cancer and 733 with no cancer, and confirmed a high sensitivity and specificity of 0.874 and 0.978, respectively. The sensitivity increased incrementally by cancer stage — 0.768 for stage I, 0.840 for stage II, 0.923 for stage III, and 0.971 for stage IV.

The test identified the tissue of origin with high accuracy, the researchers noted, but cautioned that the test needs “to be further validated in a prospective cohort study.”

MCED in Low-Income Settings

The session also featured findings on a new affordable MCED test called OncoSeek, which could provide greater access to cancer testing in low- and middle-income countries.

The OncoSeek algorithm identifies the presence of cancer using seven protein tumor markers alongside clinical information, such as gender and age. Like other tests, the test also predicts the possible tissue of origin.

The test can be run on clinical protein assay instruments that are already widely available, such as Roche cobas analyzer, Mao Mao, MD, PhD, the founder and CEO of SeekIn, of Shenzhen, China, told this news organization.

This “feature makes the test accessible worldwide, even in low- and middle-income countries,” he said. “These instruments are fully-automated and part of today’s clinical practice. Therefore, the test does not require additional infrastructure building and lab personal training.”

Another notable advantage: the OncoSeek test only costs about $20, compared with other MCED tests, which can cost anywhere from $200 to $1000.

To validate the technology in a large, diverse cohort, Dr. Mao and colleagues enrolled approximately 10,000 participants, including 2003 cancer cases and 7888 non-cancer cases.

Peripheral blood was collected from each participant and analyzed using a panel of the seven protein tumor markers — AFP, CA125, CA15-3, CA19-9, CA72-4, CEA, and CYFRA 21-1.

To reduce the risk for false positive findings, the team designed the OncoSeek algorithm to achieve a specificity of 93%. Dr. Mao and colleagues found a sensitivity of 51.7%, resulting in an overall accuracy of 84.6%.

The performance was consistent in additional validation cohorts in Brazil, China, and the United States, with sensitivities ranging from 39.0% to 77.6% for detecting nine common cancer types, including breast, colorectal, liver, lung, lymphoma, esophagus, ovary, pancreas, and stomach. The sensitivity for pancreatic cancer was at the high end of 77.6%.

The test could predict the tissue of origin in about two thirds of cases. 

Given its low cost, OncoSeek represents an affordable and accessible option for cancer screening, the authors concluded. 

Overall, “I think MCEDs have the potential to enhance cancer screening,” Dr. Wood told this news organization.

Still, questions remain about the optimal use of these tests, such as whether they are best for average-risk or higher risk populations, and how to integrate them into standard screening, she said. 

Dr. Wood also cautioned that the studies presented in the session represent early data, and it is likely that the numbers, such as sensitivity and specificity, will change with further prospective analyses.

And ultimately, these tests should complement, not replace, standard screening. “A negative testing should not be taken as a sign to avoid standard screening,” Dr. Wood said.

Dr. Yang is an employee of Geneseeq Technology, Inc., and Dr. Mao is an employee of SeekIn. Dr. Wood had no disclosures to report.

A version of this article appeared on Medscape.com.

Early data suggested that several new multicancer early detection (MCED) tests in development show promise for identifying cancers that lack routine screening options.

Analyses presented during a session at the American Association for Cancer Research annual meeting, revealed that three new MCED tests — CanScan, MERCURY, and OncoSeek — could detect a range of cancers and recognize the tissue of origin with high accuracy. One — OncoSeek — could also provide an affordable cancer screening option for individuals living in lower-income countries.

The need for these noninvasive liquid biopsy tests that can accurately identify multiple cancer types with a single blood draw, especially cancers without routine screening strategies, is pressing. “We know that the current cancer standard of care screening will identify less than 50% of all cancers, while more than 50% of all cancer deaths occur in types of cancer with no recommended screening,” said co-moderator Marie E. Wood, MD, of the University of Colorado Anschutz Medical Campus, in Aurora, Colorado.

That being said, “the clinical utility of multicancer detection tests has not been established and we’re concerned about issues of overdiagnosis and overtreatment,” she noted.

The Early Data 

One new MCED test called CanScan, developed by Geneseeq Technology, uses plasma cell-free DNA fragment patterns to detect cancer signals as well as identify the tissue of origin across 13 cancer types.

Overall, the CanScan test covers cancer types that contribute to two thirds of new cancer cases and 74% of morality globally, said presenter Shanshan Yang, of Geneseeq Research Institute, in Nanjing, China.

However, only five of these cancer types have screening recommendations issued by the US Preventive Services Task Force (USPSTF), Dr. Yang added.

The interim data comes from an ongoing large-scale prospective study evaluating the MCED test in a cohort of asymptomatic individuals between ages 45 and 75 years with an average risk for cancer and no cancer-related symptoms on enrollment.

Patients at baseline had their blood collected for the CanScan test and subsequently received annual routine physical exams once a year for 3 consecutive years, with an additional 2 years of follow-up. 

The analysis included 3724 participants with analyzable samples at the data cutoff in September 2023. Among the 3724 participants, 29 had confirmed cancer diagnoses. Among these cases, 14 patients had their cancer confirmed through USPSTF recommended screening and 15 were detected through outside of standard USPSTF screening, such as a thyroid ultrasound, Dr. Yang explained.

Almost 90% of the cancers (26 of 29) were detected in the stage I or II, and eight (27.5%) were not one of the test’s 13 targeted cancer types.

The CanScan test had a sensitivity of 55.2%, identifying 16 of 29 of the patients with cancer, including 10 of 21 individuals with stage I (47.6%), and two of three with stage II (66.7%). 

The test had a high specificity of 97.9%, meaning out of 100 people screened, only two had false negative findings.

Among the 15 patients who had their cancer detected outside of USPSTF screening recommendations, eight (53.3%) were found using a CanScan test, including patients with liver and endometrial cancers.

Compared with a positive predictive value of (PPV) of 1.6% with screening or physical exam methods alone, the CanScan test had a PPV of 17.4%, Dr. Yang reported. 

“The MCED test holds significant potential for early cancer screening in asymptomatic populations,” Dr. Yang and colleagues concluded.

Another new MCED test called MERCURY, also developed by Geneseeq Technology and presented during the session, used a similar method to detect cancer signals and predict the tissue of origin across 13 cancer types.

The researchers initially validated the test using 3076 patients with cancer and 3477 healthy controls with a target specificity of 99%. In this group, researchers reported a sensitivity of 0.865 and a specificity of 0.989.

The team then performed an independent validation analysis with 1465 participants, 732 with cancer and 733 with no cancer, and confirmed a high sensitivity and specificity of 0.874 and 0.978, respectively. The sensitivity increased incrementally by cancer stage — 0.768 for stage I, 0.840 for stage II, 0.923 for stage III, and 0.971 for stage IV.

The test identified the tissue of origin with high accuracy, the researchers noted, but cautioned that the test needs “to be further validated in a prospective cohort study.”

MCED in Low-Income Settings

The session also featured findings on a new affordable MCED test called OncoSeek, which could provide greater access to cancer testing in low- and middle-income countries.

The OncoSeek algorithm identifies the presence of cancer using seven protein tumor markers alongside clinical information, such as gender and age. Like other tests, the test also predicts the possible tissue of origin.

The test can be run on clinical protein assay instruments that are already widely available, such as Roche cobas analyzer, Mao Mao, MD, PhD, the founder and CEO of SeekIn, of Shenzhen, China, told this news organization.

This “feature makes the test accessible worldwide, even in low- and middle-income countries,” he said. “These instruments are fully-automated and part of today’s clinical practice. Therefore, the test does not require additional infrastructure building and lab personal training.”

Another notable advantage: the OncoSeek test only costs about $20, compared with other MCED tests, which can cost anywhere from $200 to $1000.

To validate the technology in a large, diverse cohort, Dr. Mao and colleagues enrolled approximately 10,000 participants, including 2003 cancer cases and 7888 non-cancer cases.

Peripheral blood was collected from each participant and analyzed using a panel of the seven protein tumor markers — AFP, CA125, CA15-3, CA19-9, CA72-4, CEA, and CYFRA 21-1.

To reduce the risk for false positive findings, the team designed the OncoSeek algorithm to achieve a specificity of 93%. Dr. Mao and colleagues found a sensitivity of 51.7%, resulting in an overall accuracy of 84.6%.

The performance was consistent in additional validation cohorts in Brazil, China, and the United States, with sensitivities ranging from 39.0% to 77.6% for detecting nine common cancer types, including breast, colorectal, liver, lung, lymphoma, esophagus, ovary, pancreas, and stomach. The sensitivity for pancreatic cancer was at the high end of 77.6%.

The test could predict the tissue of origin in about two thirds of cases. 

Given its low cost, OncoSeek represents an affordable and accessible option for cancer screening, the authors concluded. 

Overall, “I think MCEDs have the potential to enhance cancer screening,” Dr. Wood told this news organization.

Still, questions remain about the optimal use of these tests, such as whether they are best for average-risk or higher risk populations, and how to integrate them into standard screening, she said. 

Dr. Wood also cautioned that the studies presented in the session represent early data, and it is likely that the numbers, such as sensitivity and specificity, will change with further prospective analyses.

And ultimately, these tests should complement, not replace, standard screening. “A negative testing should not be taken as a sign to avoid standard screening,” Dr. Wood said.

Dr. Yang is an employee of Geneseeq Technology, Inc., and Dr. Mao is an employee of SeekIn. Dr. Wood had no disclosures to report.

A version of this article appeared on Medscape.com.

Early data suggested that several new multicancer early detection (MCED) tests in development show promise for identifying cancers that lack routine screening options.

Analyses presented during a session at the American Association for Cancer Research annual meeting, revealed that three new MCED tests — CanScan, MERCURY, and OncoSeek — could detect a range of cancers and recognize the tissue of origin with high accuracy. One — OncoSeek — could also provide an affordable cancer screening option for individuals living in lower-income countries.

The need for these noninvasive liquid biopsy tests that can accurately identify multiple cancer types with a single blood draw, especially cancers without routine screening strategies, is pressing. “We know that the current cancer standard of care screening will identify less than 50% of all cancers, while more than 50% of all cancer deaths occur in types of cancer with no recommended screening,” said co-moderator Marie E. Wood, MD, of the University of Colorado Anschutz Medical Campus, in Aurora, Colorado.

That being said, “the clinical utility of multicancer detection tests has not been established and we’re concerned about issues of overdiagnosis and overtreatment,” she noted.

The Early Data 

One new MCED test called CanScan, developed by Geneseeq Technology, uses plasma cell-free DNA fragment patterns to detect cancer signals as well as identify the tissue of origin across 13 cancer types.

Overall, the CanScan test covers cancer types that contribute to two thirds of new cancer cases and 74% of morality globally, said presenter Shanshan Yang, of Geneseeq Research Institute, in Nanjing, China.

However, only five of these cancer types have screening recommendations issued by the US Preventive Services Task Force (USPSTF), Dr. Yang added.

The interim data comes from an ongoing large-scale prospective study evaluating the MCED test in a cohort of asymptomatic individuals between ages 45 and 75 years with an average risk for cancer and no cancer-related symptoms on enrollment.

Patients at baseline had their blood collected for the CanScan test and subsequently received annual routine physical exams once a year for 3 consecutive years, with an additional 2 years of follow-up. 

The analysis included 3724 participants with analyzable samples at the data cutoff in September 2023. Among the 3724 participants, 29 had confirmed cancer diagnoses. Among these cases, 14 patients had their cancer confirmed through USPSTF recommended screening and 15 were detected through outside of standard USPSTF screening, such as a thyroid ultrasound, Dr. Yang explained.

Almost 90% of the cancers (26 of 29) were detected in the stage I or II, and eight (27.5%) were not one of the test’s 13 targeted cancer types.

The CanScan test had a sensitivity of 55.2%, identifying 16 of 29 of the patients with cancer, including 10 of 21 individuals with stage I (47.6%), and two of three with stage II (66.7%). 

The test had a high specificity of 97.9%, meaning out of 100 people screened, only two had false negative findings.

Among the 15 patients who had their cancer detected outside of USPSTF screening recommendations, eight (53.3%) were found using a CanScan test, including patients with liver and endometrial cancers.

Compared with a positive predictive value of (PPV) of 1.6% with screening or physical exam methods alone, the CanScan test had a PPV of 17.4%, Dr. Yang reported. 

“The MCED test holds significant potential for early cancer screening in asymptomatic populations,” Dr. Yang and colleagues concluded.

Another new MCED test called MERCURY, also developed by Geneseeq Technology and presented during the session, used a similar method to detect cancer signals and predict the tissue of origin across 13 cancer types.

The researchers initially validated the test using 3076 patients with cancer and 3477 healthy controls with a target specificity of 99%. In this group, researchers reported a sensitivity of 0.865 and a specificity of 0.989.

The team then performed an independent validation analysis with 1465 participants, 732 with cancer and 733 with no cancer, and confirmed a high sensitivity and specificity of 0.874 and 0.978, respectively. The sensitivity increased incrementally by cancer stage — 0.768 for stage I, 0.840 for stage II, 0.923 for stage III, and 0.971 for stage IV.

The test identified the tissue of origin with high accuracy, the researchers noted, but cautioned that the test needs “to be further validated in a prospective cohort study.”

MCED in Low-Income Settings

The session also featured findings on a new affordable MCED test called OncoSeek, which could provide greater access to cancer testing in low- and middle-income countries.

The OncoSeek algorithm identifies the presence of cancer using seven protein tumor markers alongside clinical information, such as gender and age. Like other tests, the test also predicts the possible tissue of origin.

The test can be run on clinical protein assay instruments that are already widely available, such as Roche cobas analyzer, Mao Mao, MD, PhD, the founder and CEO of SeekIn, of Shenzhen, China, told this news organization.

This “feature makes the test accessible worldwide, even in low- and middle-income countries,” he said. “These instruments are fully-automated and part of today’s clinical practice. Therefore, the test does not require additional infrastructure building and lab personal training.”

Another notable advantage: the OncoSeek test only costs about $20, compared with other MCED tests, which can cost anywhere from $200 to $1000.

To validate the technology in a large, diverse cohort, Dr. Mao and colleagues enrolled approximately 10,000 participants, including 2003 cancer cases and 7888 non-cancer cases.

Peripheral blood was collected from each participant and analyzed using a panel of the seven protein tumor markers — AFP, CA125, CA15-3, CA19-9, CA72-4, CEA, and CYFRA 21-1.

To reduce the risk for false positive findings, the team designed the OncoSeek algorithm to achieve a specificity of 93%. Dr. Mao and colleagues found a sensitivity of 51.7%, resulting in an overall accuracy of 84.6%.

The performance was consistent in additional validation cohorts in Brazil, China, and the United States, with sensitivities ranging from 39.0% to 77.6% for detecting nine common cancer types, including breast, colorectal, liver, lung, lymphoma, esophagus, ovary, pancreas, and stomach. The sensitivity for pancreatic cancer was at the high end of 77.6%.

The test could predict the tissue of origin in about two thirds of cases. 

Given its low cost, OncoSeek represents an affordable and accessible option for cancer screening, the authors concluded. 

Overall, “I think MCEDs have the potential to enhance cancer screening,” Dr. Wood told this news organization.

Still, questions remain about the optimal use of these tests, such as whether they are best for average-risk or higher risk populations, and how to integrate them into standard screening, she said. 

Dr. Wood also cautioned that the studies presented in the session represent early data, and it is likely that the numbers, such as sensitivity and specificity, will change with further prospective analyses.

And ultimately, these tests should complement, not replace, standard screening. “A negative testing should not be taken as a sign to avoid standard screening,” Dr. Wood said.

Dr. Yang is an employee of Geneseeq Technology, Inc., and Dr. Mao is an employee of SeekIn. Dr. Wood had no disclosures to report.

A version of this article appeared on Medscape.com.

TOPLINE:

A recent survey highlighted ethical concerns US oncologists have about using artificial intelligence (AI) to help make cancer treatment decisions and revealed some contradictory views about how best to integrate these tools into practice. Most respondents, for instance, said patients should not be expected to understand how AI tools work, but many also felt patients could make treatment decisions based on AI-generated recommendations. Most oncologists also felt responsible for protecting patients from biased AI, but few were confident that they could do so.

METHODOLOGY:

• The US Food and Drug Administration (FDA) has  for use in various medical specialties over the past few decades, and increasingly, AI tools are being integrated into cancer care.
• However, the uptake of these tools in oncology has raised ethical questions and concerns, including challenges with AI bias, error, or misuse, as well as issues explaining how an AI model reached a result.
• In the current study, researchers asked 204 oncologists from 37 states for their views on the ethical implications of using AI for cancer care.
• Among the survey respondents, 64% were men and 63% were non-Hispanic White; 29% were from academic practices, 47% had received some education on AI use in healthcare, and 45% were familiar with clinical decision models.
• The researchers assessed respondents’ answers to various questions, including whether to provide informed consent for AI use and how oncologists would approach a scenario where the AI model and the oncologist recommended a different treatment regimen.

TAKEAWAY:

• Overall, 81% of oncologists supported having patient consent to use an AI model during treatment decisions, and 85% felt that oncologists needed to be able to explain an AI-based clinical decision model to use it in the clinic; however, only 23% felt that patients also needed to be able to explain an AI model.
• When an AI decision model recommended a different treatment regimen than the treating oncologist, the most common response (36.8%) was to present both options to the patient and let the patient decide. Oncologists from academic settings were about 2.5 times more likely than those from other settings to let the patient decide. About 34% of respondents said they would present both options but recommend the oncologist’s regimen, whereas about 22% said they would present both but recommend the AI’s regimen. A small percentage would only present the oncologist’s regimen (5%) or the AI’s regimen (about 2.5%).
• About three of four respondents (76.5%) agreed that oncologists should protect patients from biased AI tools; however, only about one of four (27.9%) felt confident they could identify biased AI models.
• Most oncologists (91%) felt that AI developers were responsible for the medico-legal problems associated with AI use; less than half (47%) said oncologists or hospitals (43%) shared this responsibility.

IN PRACTICE:

“Together, these data characterize barriers that may impede the ethical adoption of AI into cancer care. The findings suggest that the implementation of AI in oncology must include rigorous assessments of its effect on care decisions, as well as decisional responsibility when problems related to AI use arise,” the authors concluded.

SOURCE:

The study, with first author Andrew Hantel, MD, from Dana-Farber Cancer Institute, Boston, was published last month in JAMA Network Open.

LIMITATIONS:

The study had a moderate sample size and response rate, although demographics of participating oncologists appear to be nationally representative. The cross-sectional study design limited the generalizability of the findings over time as AI is integrated into cancer care.

DISCLOSURES:

The study was funded by the National Cancer Institute, the Dana-Farber McGraw/Patterson Research Fund, and the Mark Foundation Emerging Leader Award. Dr. Hantel reported receiving personal fees from AbbVie, AstraZeneca, the American Journal of Managed Care, Genentech, and GSK.

A version of this article appeared on Medscape.com.

TOPLINE:

A recent survey highlighted ethical concerns US oncologists have about using artificial intelligence (AI) to help make cancer treatment decisions and revealed some contradictory views about how best to integrate these tools into practice. Most respondents, for instance, said patients should not be expected to understand how AI tools work, but many also felt patients could make treatment decisions based on AI-generated recommendations. Most oncologists also felt responsible for protecting patients from biased AI, but few were confident that they could do so.

METHODOLOGY:

• The US Food and Drug Administration (FDA) has  for use in various medical specialties over the past few decades, and increasingly, AI tools are being integrated into cancer care.
• However, the uptake of these tools in oncology has raised ethical questions and concerns, including challenges with AI bias, error, or misuse, as well as issues explaining how an AI model reached a result.
• In the current study, researchers asked 204 oncologists from 37 states for their views on the ethical implications of using AI for cancer care.
• Among the survey respondents, 64% were men and 63% were non-Hispanic White; 29% were from academic practices, 47% had received some education on AI use in healthcare, and 45% were familiar with clinical decision models.
• The researchers assessed respondents’ answers to various questions, including whether to provide informed consent for AI use and how oncologists would approach a scenario where the AI model and the oncologist recommended a different treatment regimen.

TAKEAWAY:

• Overall, 81% of oncologists supported having patient consent to use an AI model during treatment decisions, and 85% felt that oncologists needed to be able to explain an AI-based clinical decision model to use it in the clinic; however, only 23% felt that patients also needed to be able to explain an AI model.
• When an AI decision model recommended a different treatment regimen than the treating oncologist, the most common response (36.8%) was to present both options to the patient and let the patient decide. Oncologists from academic settings were about 2.5 times more likely than those from other settings to let the patient decide. About 34% of respondents said they would present both options but recommend the oncologist’s regimen, whereas about 22% said they would present both but recommend the AI’s regimen. A small percentage would only present the oncologist’s regimen (5%) or the AI’s regimen (about 2.5%).
• About three of four respondents (76.5%) agreed that oncologists should protect patients from biased AI tools; however, only about one of four (27.9%) felt confident they could identify biased AI models.
• Most oncologists (91%) felt that AI developers were responsible for the medico-legal problems associated with AI use; less than half (47%) said oncologists or hospitals (43%) shared this responsibility.

IN PRACTICE:

“Together, these data characterize barriers that may impede the ethical adoption of AI into cancer care. The findings suggest that the implementation of AI in oncology must include rigorous assessments of its effect on care decisions, as well as decisional responsibility when problems related to AI use arise,” the authors concluded.

SOURCE:

The study, with first author Andrew Hantel, MD, from Dana-Farber Cancer Institute, Boston, was published last month in JAMA Network Open.

LIMITATIONS:

The study had a moderate sample size and response rate, although demographics of participating oncologists appear to be nationally representative. The cross-sectional study design limited the generalizability of the findings over time as AI is integrated into cancer care.

DISCLOSURES:

The study was funded by the National Cancer Institute, the Dana-Farber McGraw/Patterson Research Fund, and the Mark Foundation Emerging Leader Award. Dr. Hantel reported receiving personal fees from AbbVie, AstraZeneca, the American Journal of Managed Care, Genentech, and GSK.

A version of this article appeared on Medscape.com.

TOPLINE:

A recent survey highlighted ethical concerns US oncologists have about using artificial intelligence (AI) to help make cancer treatment decisions and revealed some contradictory views about how best to integrate these tools into practice. Most respondents, for instance, said patients should not be expected to understand how AI tools work, but many also felt patients could make treatment decisions based on AI-generated recommendations. Most oncologists also felt responsible for protecting patients from biased AI, but few were confident that they could do so.

METHODOLOGY:

• The US Food and Drug Administration (FDA) has  for use in various medical specialties over the past few decades, and increasingly, AI tools are being integrated into cancer care.
• However, the uptake of these tools in oncology has raised ethical questions and concerns, including challenges with AI bias, error, or misuse, as well as issues explaining how an AI model reached a result.
• In the current study, researchers asked 204 oncologists from 37 states for their views on the ethical implications of using AI for cancer care.
• Among the survey respondents, 64% were men and 63% were non-Hispanic White; 29% were from academic practices, 47% had received some education on AI use in healthcare, and 45% were familiar with clinical decision models.
• The researchers assessed respondents’ answers to various questions, including whether to provide informed consent for AI use and how oncologists would approach a scenario where the AI model and the oncologist recommended a different treatment regimen.

TAKEAWAY:

• Overall, 81% of oncologists supported having patient consent to use an AI model during treatment decisions, and 85% felt that oncologists needed to be able to explain an AI-based clinical decision model to use it in the clinic; however, only 23% felt that patients also needed to be able to explain an AI model.
• When an AI decision model recommended a different treatment regimen than the treating oncologist, the most common response (36.8%) was to present both options to the patient and let the patient decide. Oncologists from academic settings were about 2.5 times more likely than those from other settings to let the patient decide. About 34% of respondents said they would present both options but recommend the oncologist’s regimen, whereas about 22% said they would present both but recommend the AI’s regimen. A small percentage would only present the oncologist’s regimen (5%) or the AI’s regimen (about 2.5%).
• About three of four respondents (76.5%) agreed that oncologists should protect patients from biased AI tools; however, only about one of four (27.9%) felt confident they could identify biased AI models.
• Most oncologists (91%) felt that AI developers were responsible for the medico-legal problems associated with AI use; less than half (47%) said oncologists or hospitals (43%) shared this responsibility.

IN PRACTICE:

“Together, these data characterize barriers that may impede the ethical adoption of AI into cancer care. The findings suggest that the implementation of AI in oncology must include rigorous assessments of its effect on care decisions, as well as decisional responsibility when problems related to AI use arise,” the authors concluded.

SOURCE:

The study, with first author Andrew Hantel, MD, from Dana-Farber Cancer Institute, Boston, was published last month in JAMA Network Open.

LIMITATIONS:

The study had a moderate sample size and response rate, although demographics of participating oncologists appear to be nationally representative. The cross-sectional study design limited the generalizability of the findings over time as AI is integrated into cancer care.

DISCLOSURES:

The study was funded by the National Cancer Institute, the Dana-Farber McGraw/Patterson Research Fund, and the Mark Foundation Emerging Leader Award. Dr. Hantel reported receiving personal fees from AbbVie, AstraZeneca, the American Journal of Managed Care, Genentech, and GSK.

A version of this article appeared on Medscape.com.