Colorectal Cancer

The GLP-1 drugs widely prescribed for diabetes and weight loss might also help reduce the risk for colorectal cancer and possibly improve outcomes in people who have the disease, according to a series of studies presented at ASCO Gastrointestinal Cancers Symposium 2026.

In one study, researchers observed a 36% lower risk for colorectal cancer among people who used GLP-1 receptor agonists vs those who used aspirin — a drug long investigated for colorectal cancer primary prevention.

While aspirin has shown “modest efficacy” in that regard, it also carries a bleeding risk that limits its use, Colton Jones, MD, a hematology and oncology fellow with The University of Texas San Antonio, told conference attendees.

Emerging evidence suggests that GLP-1s possess anti-inflammatory and anti-neoplastic properties, while some recent observational studies have linked the medications to reduced risks for certain cancers, particularly obesity-related types.

However, Jones said, research into a possible role for GLP-1s in cancer risk reduction is still in the early stages.

Prevention Potential

To conduct a “real-world” analysis, Jones and his colleagues turned to the TriNetX database, which contains electronic health records from about 150 million patients at more than 100 US healthcare organizations.

The researchers created two propensity score-matched cohorts of GLP-1 users and aspirin users, with 140,828 patients (average age, 58 years) in each. None had a history of colorectal cancer, and none were using anti-inflammatory medications other than aspirin or glucose-lowering drugs other than a GLP-1.

During a median follow-up of 5-6 years, GLP-1 use was significantly associated with reduced colorectal cancer incidence compared with aspirin use (hazard ratio [HR], 0.64). The findings were similar among people considered to be at an increased colorectal cancer risk due to health or family history: In that group, GLP-1 users had a roughly 42% lower risk of the disease (HR, 0.58).

Overall, the risk reduction with GLP-1 use was seen regardless of obesity or diabetes status, but the association was strongest among people who began treatment before age 45.

When the researchers examined individual GLP-1 medications, only semaglutide (Ozempic), liraglutide (Saxenda/Victoza), and dulaglutide (Trulicity) were associated with significant risk reductions.

As for safety outcomes, aspirin users had slightly higher rates of gastrointestinal bleeding and gastric ulcers and were more likely to suffer acute kidney injury (2.8% vs 1.15% among GLP-1 users; HR, 0.37). GLP-1 users experienced more diarrhea (6.8% vs 5.4%) and abdominal pain (19% vs 16.3%) than aspirin users did.

Jones said that both the risk reduction and safety profile associated with GLP-1s “underscore a potential public health impact” and warrant prospective validation.

Study discussant Joel Saltzman, MD, an ASCO gastrointestinal cancer expert, called the findings “thought-provoking.”

Broadly, he said, the study raises important questions about how metabolic disease, obesity, and cancer risk are interconnected — and how prevention strategies might evolve as more data emerge.

“It will certainly be interesting over the upcoming years to see how [GLP-1s] fit into colorectal cancer prevention,” said Saltzman, of Taussig Cancer Center, Cleveland Clinic, Cleveland.

Improved CRC Outcomes?

Looking beyond prevention, Jones and his colleagues conducted a separate analysis of patients diagnosed with colorectal cancer, to see whether GLP-1 therapy was associated with outcomes.

In that analysis, also using the TriNetX database, they matched 5170 patients with colorectal cancer who were on GLP-1 therapy with the same number of patients who were not on a GLP-1 medication.

Over 10 years, GLP-1 use was associated with a 53% reduction in all-cause mortality compared with nonuse (HR, 0.47), corresponding to an absolute risk reduction of 5.6% and a number needed to treat of 18.

The survival benefit was consistent across age, diabetes status, BMI, cancer stage, and treatment subgroups. GLP-1 use was not associated with a statistically significant change in the risk for metastases (HR, 0.895).

Meanwhile, another study presented at the meeting, by researchers at Mayo Clinic, Jacksonville, Florida, yielded similar findings.

Researchers led by Yajur Arya, MD, focused specifically on patients with colon cancer and comorbid obesity comparing outcomes in nearly 2000 patients taking a GLP-1 with more than 16,000 matched patients who were not on a GLP-1 agent.

Over 5 years of follow-up, GLP-1 users had a lower risk for overall mortality (HR, 0.46). They also showed decreased risks for myocardial infarction (HR, 0.83), sepsis (risk difference, -3.48%), and need for mechanical ventilation (HR, 0.49).

Both Jones and Arya stressed, however, that the findings only serve to highlight possible benefits of GLP-1 use beyond diabetes and weight management. Prospective studies, they said, are needed to better understand why these associations exist, and to potentially guide practice in the future.

None of the studies had commercial funding. Jones, Arya, and Saltzman had no relevant disclosures.

A version of this article first appeared on Medscape.com.

The GLP-1 drugs widely prescribed for diabetes and weight loss might also help reduce the risk for colorectal cancer and possibly improve outcomes in people who have the disease, according to a series of studies presented at ASCO Gastrointestinal Cancers Symposium 2026.

In one study, researchers observed a 36% lower risk for colorectal cancer among people who used GLP-1 receptor agonists vs those who used aspirin — a drug long investigated for colorectal cancer primary prevention.

While aspirin has shown “modest efficacy” in that regard, it also carries a bleeding risk that limits its use, Colton Jones, MD, a hematology and oncology fellow with The University of Texas San Antonio, told conference attendees.

Emerging evidence suggests that GLP-1s possess anti-inflammatory and anti-neoplastic properties, while some recent observational studies have linked the medications to reduced risks for certain cancers, particularly obesity-related types.

However, Jones said, research into a possible role for GLP-1s in cancer risk reduction is still in the early stages.

Prevention Potential

To conduct a “real-world” analysis, Jones and his colleagues turned to the TriNetX database, which contains electronic health records from about 150 million patients at more than 100 US healthcare organizations.

The researchers created two propensity score-matched cohorts of GLP-1 users and aspirin users, with 140,828 patients (average age, 58 years) in each. None had a history of colorectal cancer, and none were using anti-inflammatory medications other than aspirin or glucose-lowering drugs other than a GLP-1.

During a median follow-up of 5-6 years, GLP-1 use was significantly associated with reduced colorectal cancer incidence compared with aspirin use (hazard ratio [HR], 0.64). The findings were similar among people considered to be at an increased colorectal cancer risk due to health or family history: In that group, GLP-1 users had a roughly 42% lower risk of the disease (HR, 0.58).

Overall, the risk reduction with GLP-1 use was seen regardless of obesity or diabetes status, but the association was strongest among people who began treatment before age 45.

When the researchers examined individual GLP-1 medications, only semaglutide (Ozempic), liraglutide (Saxenda/Victoza), and dulaglutide (Trulicity) were associated with significant risk reductions.

As for safety outcomes, aspirin users had slightly higher rates of gastrointestinal bleeding and gastric ulcers and were more likely to suffer acute kidney injury (2.8% vs 1.15% among GLP-1 users; HR, 0.37). GLP-1 users experienced more diarrhea (6.8% vs 5.4%) and abdominal pain (19% vs 16.3%) than aspirin users did.

Jones said that both the risk reduction and safety profile associated with GLP-1s “underscore a potential public health impact” and warrant prospective validation.

Study discussant Joel Saltzman, MD, an ASCO gastrointestinal cancer expert, called the findings “thought-provoking.”

Broadly, he said, the study raises important questions about how metabolic disease, obesity, and cancer risk are interconnected — and how prevention strategies might evolve as more data emerge.

“It will certainly be interesting over the upcoming years to see how [GLP-1s] fit into colorectal cancer prevention,” said Saltzman, of Taussig Cancer Center, Cleveland Clinic, Cleveland.

Improved CRC Outcomes?

Looking beyond prevention, Jones and his colleagues conducted a separate analysis of patients diagnosed with colorectal cancer, to see whether GLP-1 therapy was associated with outcomes.

In that analysis, also using the TriNetX database, they matched 5170 patients with colorectal cancer who were on GLP-1 therapy with the same number of patients who were not on a GLP-1 medication.

Over 10 years, GLP-1 use was associated with a 53% reduction in all-cause mortality compared with nonuse (HR, 0.47), corresponding to an absolute risk reduction of 5.6% and a number needed to treat of 18.

The survival benefit was consistent across age, diabetes status, BMI, cancer stage, and treatment subgroups. GLP-1 use was not associated with a statistically significant change in the risk for metastases (HR, 0.895).

Meanwhile, another study presented at the meeting, by researchers at Mayo Clinic, Jacksonville, Florida, yielded similar findings.

Researchers led by Yajur Arya, MD, focused specifically on patients with colon cancer and comorbid obesity comparing outcomes in nearly 2000 patients taking a GLP-1 with more than 16,000 matched patients who were not on a GLP-1 agent.

Over 5 years of follow-up, GLP-1 users had a lower risk for overall mortality (HR, 0.46). They also showed decreased risks for myocardial infarction (HR, 0.83), sepsis (risk difference, -3.48%), and need for mechanical ventilation (HR, 0.49).

Both Jones and Arya stressed, however, that the findings only serve to highlight possible benefits of GLP-1 use beyond diabetes and weight management. Prospective studies, they said, are needed to better understand why these associations exist, and to potentially guide practice in the future.

None of the studies had commercial funding. Jones, Arya, and Saltzman had no relevant disclosures.

A version of this article first appeared on Medscape.com.

The GLP-1 drugs widely prescribed for diabetes and weight loss might also help reduce the risk for colorectal cancer and possibly improve outcomes in people who have the disease, according to a series of studies presented at ASCO Gastrointestinal Cancers Symposium 2026.

In one study, researchers observed a 36% lower risk for colorectal cancer among people who used GLP-1 receptor agonists vs those who used aspirin — a drug long investigated for colorectal cancer primary prevention.

While aspirin has shown “modest efficacy” in that regard, it also carries a bleeding risk that limits its use, Colton Jones, MD, a hematology and oncology fellow with The University of Texas San Antonio, told conference attendees.

Emerging evidence suggests that GLP-1s possess anti-inflammatory and anti-neoplastic properties, while some recent observational studies have linked the medications to reduced risks for certain cancers, particularly obesity-related types.

However, Jones said, research into a possible role for GLP-1s in cancer risk reduction is still in the early stages.

Prevention Potential

To conduct a “real-world” analysis, Jones and his colleagues turned to the TriNetX database, which contains electronic health records from about 150 million patients at more than 100 US healthcare organizations.

The researchers created two propensity score-matched cohorts of GLP-1 users and aspirin users, with 140,828 patients (average age, 58 years) in each. None had a history of colorectal cancer, and none were using anti-inflammatory medications other than aspirin or glucose-lowering drugs other than a GLP-1.

During a median follow-up of 5-6 years, GLP-1 use was significantly associated with reduced colorectal cancer incidence compared with aspirin use (hazard ratio [HR], 0.64). The findings were similar among people considered to be at an increased colorectal cancer risk due to health or family history: In that group, GLP-1 users had a roughly 42% lower risk of the disease (HR, 0.58).

Overall, the risk reduction with GLP-1 use was seen regardless of obesity or diabetes status, but the association was strongest among people who began treatment before age 45.

When the researchers examined individual GLP-1 medications, only semaglutide (Ozempic), liraglutide (Saxenda/Victoza), and dulaglutide (Trulicity) were associated with significant risk reductions.

As for safety outcomes, aspirin users had slightly higher rates of gastrointestinal bleeding and gastric ulcers and were more likely to suffer acute kidney injury (2.8% vs 1.15% among GLP-1 users; HR, 0.37). GLP-1 users experienced more diarrhea (6.8% vs 5.4%) and abdominal pain (19% vs 16.3%) than aspirin users did.

Jones said that both the risk reduction and safety profile associated with GLP-1s “underscore a potential public health impact” and warrant prospective validation.

Study discussant Joel Saltzman, MD, an ASCO gastrointestinal cancer expert, called the findings “thought-provoking.”

Broadly, he said, the study raises important questions about how metabolic disease, obesity, and cancer risk are interconnected — and how prevention strategies might evolve as more data emerge.

“It will certainly be interesting over the upcoming years to see how [GLP-1s] fit into colorectal cancer prevention,” said Saltzman, of Taussig Cancer Center, Cleveland Clinic, Cleveland.

Improved CRC Outcomes?

Looking beyond prevention, Jones and his colleagues conducted a separate analysis of patients diagnosed with colorectal cancer, to see whether GLP-1 therapy was associated with outcomes.

In that analysis, also using the TriNetX database, they matched 5170 patients with colorectal cancer who were on GLP-1 therapy with the same number of patients who were not on a GLP-1 medication.

Over 10 years, GLP-1 use was associated with a 53% reduction in all-cause mortality compared with nonuse (HR, 0.47), corresponding to an absolute risk reduction of 5.6% and a number needed to treat of 18.

The survival benefit was consistent across age, diabetes status, BMI, cancer stage, and treatment subgroups. GLP-1 use was not associated with a statistically significant change in the risk for metastases (HR, 0.895).

Meanwhile, another study presented at the meeting, by researchers at Mayo Clinic, Jacksonville, Florida, yielded similar findings.

Researchers led by Yajur Arya, MD, focused specifically on patients with colon cancer and comorbid obesity comparing outcomes in nearly 2000 patients taking a GLP-1 with more than 16,000 matched patients who were not on a GLP-1 agent.

Over 5 years of follow-up, GLP-1 users had a lower risk for overall mortality (HR, 0.46). They also showed decreased risks for myocardial infarction (HR, 0.83), sepsis (risk difference, -3.48%), and need for mechanical ventilation (HR, 0.49).

Both Jones and Arya stressed, however, that the findings only serve to highlight possible benefits of GLP-1 use beyond diabetes and weight management. Prospective studies, they said, are needed to better understand why these associations exist, and to potentially guide practice in the future.

None of the studies had commercial funding. Jones, Arya, and Saltzman had no relevant disclosures.

A version of this article first appeared on Medscape.com.

Regular physical activity—especially walking—may improve fatigue and boost quality of life for people with nonmetastatic colorectal cancer during the first 2 years after diagnosis, according to research presented at ASCO Gastrointestinal Cancers Symposium 2026.

The study, which tracked over 1700 patients with colorectal cancer, found that those with nonmetastatic disease who walked for exercise 6-12 months after their diagnosis showed significant improvement in their fatigue scores over time. Their quality-of-life ratings rose in tandem.

The findings suggest that simple, sustained movement may play a meaningful role in long-term survivorship care, lead investigator Louisa Liu, MD, of Cedars-Sinai Medical Center in Los Angeles, said during a press briefing.

“Fatigue is one of the most common and debilitating symptoms our patients experience, often long after treatment ends,” Liu noted.

The new data, she said, show that an accessible form of exercise, especially when maintained over time, “can make a real difference in how patients feel and function during recovery.”

Joel Saltzman, MD, an ASCO expert in gastrointestinal cancers based at Taussig Cancer Center, Cleveland Clinic, Cleveland, agreed.

This is a “super-important study for all of us in the cancer community,” Saltzman told the briefing, especially in light of the CHALLENGE trial.

That study demonstrated that a structured exercise program can actually improve overall survival for patients with early-stage colon cancer who completed surgery and adjuvant chemotherapy.

“When you couple that with how patients feel, it really begs the question: Are we as a society doing enough cancer rehabilitation?” Saltzman said. “Everyone’s familiar with cardiac rehab, but oncologic rehabilitation is really something that really should be thought about in the future.”

Among long-term colorectal cancer survivors, nearly 40% continue to experience moderate-to-severe fatigue years after treatment — a challenge that affects functional recovery, daily activity, and quality of life.

“Yet,” Liu said, “our toolbox of effective interventions remains limited.”

Growing evidence supports physical activity as a nonpharmacologic approach for managing cancer-related fatigue. The mechanisms, Liu noted, may be multiple and include reductions in systemic inflammation, preserved muscle mass, better sleep quality and improvements in psychological stress.

In fact, current clinical guidelines recommend physical activity as part of survivorship care, but some key questions remain unanswered, Liu said.

“We still don’t fully understand when during recovery activity is most beneficial, what types of activity are best for different patients, or how these effects play out in real-world longitudinal settings, especially in colorectal cancer survivors,” she explained.

To address some of those gaps, Liu and colleagues analyzed data from 1718 patients with colorectal cancer (mean age, 67 years; 48% women) enrolled in the International ColoCare prospective cohort study. Nearly 1 in 5 had metastatic disease at diagnosis.

Physical activity was assessed at baseline and at 6, 12, and 24 months after diagnosis using a validated questionnaire. Participants’ total number of metabolic equivalent of task (MET) minutes per week — a measurement of energy spent during physical activity — were calculated for walking, moderate activities, and vigorous activities.

Total physical activity was categorized as low (fewer than 600 MET min/wk), moderate (600-3000 MET min/wk), or high (over 3000 MET min/wk).

Cancer-related fatigue and quality of life were measured using the European Organization for Research and Treatment of Cancer QLQ-C30 scale.

Overall, patients who were more physically active reported less fatigue and better quality of life as they moved further into recovery. And walking, Liu said, showed the “clearest and most consistent” association with these improved outcomes.

Among patients with nonmetastatic disease, those who reported regular walking 6-12 months after diagnosis showed significantly lower fatigue and higher quality-of-life scores over 2 years. Fatigue scores in this group improved steadily with time, from 32.5 at diagnosis to 29 at 12 months post-diagnosis and 26.8 at 24 months post-diagnosis.

Patients with metastatic disease also showed reductions in fatigue scores — from 40.7 at diagnosis to 37.1 at 12 months and 36.4 at 24 months — although those differences did not reach statistical significance.

Liu pointed out that patients with metastatic disease, not surprisingly, reported greater fatigue and poorer quality of life across all time points vs those with early-stage disease.

So, she said, “we don’t yet have strong evidence that physical activity changes the fatigue trajectory in the long run for metastatic patients. But this is an area where more targeted research is really needed.”

Looking at patterns of physical activity, the researchers found that activity levels at the time of diagnosis did not reliably predict long-term fatigue and quality-of-life outcomes. Instead, a patient’s activity level maintained between diagnosis and 1 year follow-up was a predictor of better outcomes.

“Short-term increases in physical activity didn’t seem to make a meaningful difference,” Liu said. “This suggests that when it comes to managing cancer-related fatigue, the key is to build steady, lasting habits that patients can stick with throughout their recovery.”

The study had no commercial funding. Liu and Saltzman had no disclosures.

A version of this article first appeared on Medscape.com.

Regular physical activity—especially walking—may improve fatigue and boost quality of life for people with nonmetastatic colorectal cancer during the first 2 years after diagnosis, according to research presented at ASCO Gastrointestinal Cancers Symposium 2026.

The study, which tracked over 1700 patients with colorectal cancer, found that those with nonmetastatic disease who walked for exercise 6-12 months after their diagnosis showed significant improvement in their fatigue scores over time. Their quality-of-life ratings rose in tandem.

The findings suggest that simple, sustained movement may play a meaningful role in long-term survivorship care, lead investigator Louisa Liu, MD, of Cedars-Sinai Medical Center in Los Angeles, said during a press briefing.

“Fatigue is one of the most common and debilitating symptoms our patients experience, often long after treatment ends,” Liu noted.

The new data, she said, show that an accessible form of exercise, especially when maintained over time, “can make a real difference in how patients feel and function during recovery.”

Joel Saltzman, MD, an ASCO expert in gastrointestinal cancers based at Taussig Cancer Center, Cleveland Clinic, Cleveland, agreed.

This is a “super-important study for all of us in the cancer community,” Saltzman told the briefing, especially in light of the CHALLENGE trial.

That study demonstrated that a structured exercise program can actually improve overall survival for patients with early-stage colon cancer who completed surgery and adjuvant chemotherapy.

“When you couple that with how patients feel, it really begs the question: Are we as a society doing enough cancer rehabilitation?” Saltzman said. “Everyone’s familiar with cardiac rehab, but oncologic rehabilitation is really something that really should be thought about in the future.”

Among long-term colorectal cancer survivors, nearly 40% continue to experience moderate-to-severe fatigue years after treatment — a challenge that affects functional recovery, daily activity, and quality of life.

“Yet,” Liu said, “our toolbox of effective interventions remains limited.”

Growing evidence supports physical activity as a nonpharmacologic approach for managing cancer-related fatigue. The mechanisms, Liu noted, may be multiple and include reductions in systemic inflammation, preserved muscle mass, better sleep quality and improvements in psychological stress.

In fact, current clinical guidelines recommend physical activity as part of survivorship care, but some key questions remain unanswered, Liu said.

“We still don’t fully understand when during recovery activity is most beneficial, what types of activity are best for different patients, or how these effects play out in real-world longitudinal settings, especially in colorectal cancer survivors,” she explained.

To address some of those gaps, Liu and colleagues analyzed data from 1718 patients with colorectal cancer (mean age, 67 years; 48% women) enrolled in the International ColoCare prospective cohort study. Nearly 1 in 5 had metastatic disease at diagnosis.

Physical activity was assessed at baseline and at 6, 12, and 24 months after diagnosis using a validated questionnaire. Participants’ total number of metabolic equivalent of task (MET) minutes per week — a measurement of energy spent during physical activity — were calculated for walking, moderate activities, and vigorous activities.

Total physical activity was categorized as low (fewer than 600 MET min/wk), moderate (600-3000 MET min/wk), or high (over 3000 MET min/wk).

Cancer-related fatigue and quality of life were measured using the European Organization for Research and Treatment of Cancer QLQ-C30 scale.

Overall, patients who were more physically active reported less fatigue and better quality of life as they moved further into recovery. And walking, Liu said, showed the “clearest and most consistent” association with these improved outcomes.

Among patients with nonmetastatic disease, those who reported regular walking 6-12 months after diagnosis showed significantly lower fatigue and higher quality-of-life scores over 2 years. Fatigue scores in this group improved steadily with time, from 32.5 at diagnosis to 29 at 12 months post-diagnosis and 26.8 at 24 months post-diagnosis.

Patients with metastatic disease also showed reductions in fatigue scores — from 40.7 at diagnosis to 37.1 at 12 months and 36.4 at 24 months — although those differences did not reach statistical significance.

Liu pointed out that patients with metastatic disease, not surprisingly, reported greater fatigue and poorer quality of life across all time points vs those with early-stage disease.

So, she said, “we don’t yet have strong evidence that physical activity changes the fatigue trajectory in the long run for metastatic patients. But this is an area where more targeted research is really needed.”

Looking at patterns of physical activity, the researchers found that activity levels at the time of diagnosis did not reliably predict long-term fatigue and quality-of-life outcomes. Instead, a patient’s activity level maintained between diagnosis and 1 year follow-up was a predictor of better outcomes.

“Short-term increases in physical activity didn’t seem to make a meaningful difference,” Liu said. “This suggests that when it comes to managing cancer-related fatigue, the key is to build steady, lasting habits that patients can stick with throughout their recovery.”

The study had no commercial funding. Liu and Saltzman had no disclosures.

A version of this article first appeared on Medscape.com.

Regular physical activity—especially walking—may improve fatigue and boost quality of life for people with nonmetastatic colorectal cancer during the first 2 years after diagnosis, according to research presented at ASCO Gastrointestinal Cancers Symposium 2026.

The study, which tracked over 1700 patients with colorectal cancer, found that those with nonmetastatic disease who walked for exercise 6-12 months after their diagnosis showed significant improvement in their fatigue scores over time. Their quality-of-life ratings rose in tandem.

The findings suggest that simple, sustained movement may play a meaningful role in long-term survivorship care, lead investigator Louisa Liu, MD, of Cedars-Sinai Medical Center in Los Angeles, said during a press briefing.

“Fatigue is one of the most common and debilitating symptoms our patients experience, often long after treatment ends,” Liu noted.

The new data, she said, show that an accessible form of exercise, especially when maintained over time, “can make a real difference in how patients feel and function during recovery.”

Joel Saltzman, MD, an ASCO expert in gastrointestinal cancers based at Taussig Cancer Center, Cleveland Clinic, Cleveland, agreed.

This is a “super-important study for all of us in the cancer community,” Saltzman told the briefing, especially in light of the CHALLENGE trial.

That study demonstrated that a structured exercise program can actually improve overall survival for patients with early-stage colon cancer who completed surgery and adjuvant chemotherapy.

“When you couple that with how patients feel, it really begs the question: Are we as a society doing enough cancer rehabilitation?” Saltzman said. “Everyone’s familiar with cardiac rehab, but oncologic rehabilitation is really something that really should be thought about in the future.”

Among long-term colorectal cancer survivors, nearly 40% continue to experience moderate-to-severe fatigue years after treatment — a challenge that affects functional recovery, daily activity, and quality of life.

“Yet,” Liu said, “our toolbox of effective interventions remains limited.”

Growing evidence supports physical activity as a nonpharmacologic approach for managing cancer-related fatigue. The mechanisms, Liu noted, may be multiple and include reductions in systemic inflammation, preserved muscle mass, better sleep quality and improvements in psychological stress.

In fact, current clinical guidelines recommend physical activity as part of survivorship care, but some key questions remain unanswered, Liu said.

“We still don’t fully understand when during recovery activity is most beneficial, what types of activity are best for different patients, or how these effects play out in real-world longitudinal settings, especially in colorectal cancer survivors,” she explained.

To address some of those gaps, Liu and colleagues analyzed data from 1718 patients with colorectal cancer (mean age, 67 years; 48% women) enrolled in the International ColoCare prospective cohort study. Nearly 1 in 5 had metastatic disease at diagnosis.

Physical activity was assessed at baseline and at 6, 12, and 24 months after diagnosis using a validated questionnaire. Participants’ total number of metabolic equivalent of task (MET) minutes per week — a measurement of energy spent during physical activity — were calculated for walking, moderate activities, and vigorous activities.

Total physical activity was categorized as low (fewer than 600 MET min/wk), moderate (600-3000 MET min/wk), or high (over 3000 MET min/wk).

Cancer-related fatigue and quality of life were measured using the European Organization for Research and Treatment of Cancer QLQ-C30 scale.

Overall, patients who were more physically active reported less fatigue and better quality of life as they moved further into recovery. And walking, Liu said, showed the “clearest and most consistent” association with these improved outcomes.

Among patients with nonmetastatic disease, those who reported regular walking 6-12 months after diagnosis showed significantly lower fatigue and higher quality-of-life scores over 2 years. Fatigue scores in this group improved steadily with time, from 32.5 at diagnosis to 29 at 12 months post-diagnosis and 26.8 at 24 months post-diagnosis.

Patients with metastatic disease also showed reductions in fatigue scores — from 40.7 at diagnosis to 37.1 at 12 months and 36.4 at 24 months — although those differences did not reach statistical significance.

Liu pointed out that patients with metastatic disease, not surprisingly, reported greater fatigue and poorer quality of life across all time points vs those with early-stage disease.

So, she said, “we don’t yet have strong evidence that physical activity changes the fatigue trajectory in the long run for metastatic patients. But this is an area where more targeted research is really needed.”

Looking at patterns of physical activity, the researchers found that activity levels at the time of diagnosis did not reliably predict long-term fatigue and quality-of-life outcomes. Instead, a patient’s activity level maintained between diagnosis and 1 year follow-up was a predictor of better outcomes.

“Short-term increases in physical activity didn’t seem to make a meaningful difference,” Liu said. “This suggests that when it comes to managing cancer-related fatigue, the key is to build steady, lasting habits that patients can stick with throughout their recovery.”

The study had no commercial funding. Liu and Saltzman had no disclosures.

A version of this article first appeared on Medscape.com.

TOPLINE:

Among patients with ulcerative colitis (UC) who develop colorectal cancer (CRC), greater background mucosal inflammation at the time of CRC diagnosis is associated with progressively worse survival outcomes, with tumors arising within the UC-involved segment having worse prognosis.

METHODOLOGY:

• Patients with UC are at an increased risk for CRC, with risk influenced by the extent and intensity of underlying mucosal inflammation.
• Researchers retrospectively reviewed medical records of patients with UC diagnosed with CRC between 1983 and 2020 at 43 institutions across Japan to determine whether inflammation at cancer diagnosis affected prognosis.
• After endoscopic assessment, tumors were classified as arising inside the UC‑involved segment at diagnosis (within‑area tumors) or outside that segment (outside‑area tumors).
• The Mayo endoscopic score (MES) was used to grade background mucosal inflammation in the within‑area group as inactive (MES 0), mild-moderate (MES 1-2), or severe (MES 3).
• The primary endpoint was 5-year recurrence-free survival, and the secondary endpoint was 5-year cancer-specific survival.

TAKEAWAY:

• Among 723 patients followed for a median of 51 months, 683 had within-area tumors (mean age at CRC diagnosis, 51.8 years; 61.9% male) and 40 had outside-area tumors (mean age at CRC diagnosis, 61.1 years; 60.0% male).
• The within-area group had lower rate of 5-year recurrence-free survival than the outside-area group (75.1% vs 87.6%; P = .022), and lower rate of 5-year cancer-specific survival (81.1% vs 94.3%; P = .038).
• Within-area tumor location independently predicted worse recurrence-free survival (adjusted hazard ratio, 2.99; P = .030).
• In the within‑area group, higher MES was associated with stepwise (although nonsignificant) declines in recurrence‑free survival (inactive, 84.4%; mild-moderate, 79.4%; severe, 73.8%; P = .150). Corresponding cancer‑specific survival rates in these groups declined significantly (89.0%, 84.8%, and 73.8%, respectively; P = .048).

IN PRACTICE:

“These findings shift the clinical focus from inflammation as a risk factor for carcinogenesis to inflammation as a prognostic determinant, highlighting a potential new role for systematic endoscopic assessment of the background mucosa at cancer diagnosis,” the authors wrote.

SOURCE:

This study was led by Akiyoshi Ikebata, Department of Surgery, Keio University School of Medicine, Tokyo, Japan. It was published online in December 2025, in the Journal of Crohn's and Colitis.

LIMITATIONS:

The retrospective design introduced potential for unmeasured confounding and selection bias. The MES was assigned by local physicians without central review, which may have introduced variability. The small size of the outside‑area tumor group increased the risk for baseline imbalances.

DISCLOSURES:

No specific funding source was reported. The authors declared having no conflicts of interest.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.

A version of this article first appeared on Medscape.com.

TOPLINE:

Among patients with ulcerative colitis (UC) who develop colorectal cancer (CRC), greater background mucosal inflammation at the time of CRC diagnosis is associated with progressively worse survival outcomes, with tumors arising within the UC-involved segment having worse prognosis.

METHODOLOGY:

• Patients with UC are at an increased risk for CRC, with risk influenced by the extent and intensity of underlying mucosal inflammation.
• Researchers retrospectively reviewed medical records of patients with UC diagnosed with CRC between 1983 and 2020 at 43 institutions across Japan to determine whether inflammation at cancer diagnosis affected prognosis.
• After endoscopic assessment, tumors were classified as arising inside the UC‑involved segment at diagnosis (within‑area tumors) or outside that segment (outside‑area tumors).
• The Mayo endoscopic score (MES) was used to grade background mucosal inflammation in the within‑area group as inactive (MES 0), mild-moderate (MES 1-2), or severe (MES 3).
• The primary endpoint was 5-year recurrence-free survival, and the secondary endpoint was 5-year cancer-specific survival.

TAKEAWAY:

• Among 723 patients followed for a median of 51 months, 683 had within-area tumors (mean age at CRC diagnosis, 51.8 years; 61.9% male) and 40 had outside-area tumors (mean age at CRC diagnosis, 61.1 years; 60.0% male).
• The within-area group had lower rate of 5-year recurrence-free survival than the outside-area group (75.1% vs 87.6%; P = .022), and lower rate of 5-year cancer-specific survival (81.1% vs 94.3%; P = .038).
• Within-area tumor location independently predicted worse recurrence-free survival (adjusted hazard ratio, 2.99; P = .030).
• In the within‑area group, higher MES was associated with stepwise (although nonsignificant) declines in recurrence‑free survival (inactive, 84.4%; mild-moderate, 79.4%; severe, 73.8%; P = .150). Corresponding cancer‑specific survival rates in these groups declined significantly (89.0%, 84.8%, and 73.8%, respectively; P = .048).

IN PRACTICE:

“These findings shift the clinical focus from inflammation as a risk factor for carcinogenesis to inflammation as a prognostic determinant, highlighting a potential new role for systematic endoscopic assessment of the background mucosa at cancer diagnosis,” the authors wrote.

SOURCE:

This study was led by Akiyoshi Ikebata, Department of Surgery, Keio University School of Medicine, Tokyo, Japan. It was published online in December 2025, in the Journal of Crohn's and Colitis.

LIMITATIONS:

The retrospective design introduced potential for unmeasured confounding and selection bias. The MES was assigned by local physicians without central review, which may have introduced variability. The small size of the outside‑area tumor group increased the risk for baseline imbalances.

DISCLOSURES:

No specific funding source was reported. The authors declared having no conflicts of interest.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.

A version of this article first appeared on Medscape.com.

TOPLINE:

Among patients with ulcerative colitis (UC) who develop colorectal cancer (CRC), greater background mucosal inflammation at the time of CRC diagnosis is associated with progressively worse survival outcomes, with tumors arising within the UC-involved segment having worse prognosis.

METHODOLOGY:

• Patients with UC are at an increased risk for CRC, with risk influenced by the extent and intensity of underlying mucosal inflammation.
• Researchers retrospectively reviewed medical records of patients with UC diagnosed with CRC between 1983 and 2020 at 43 institutions across Japan to determine whether inflammation at cancer diagnosis affected prognosis.
• After endoscopic assessment, tumors were classified as arising inside the UC‑involved segment at diagnosis (within‑area tumors) or outside that segment (outside‑area tumors).
• The Mayo endoscopic score (MES) was used to grade background mucosal inflammation in the within‑area group as inactive (MES 0), mild-moderate (MES 1-2), or severe (MES 3).
• The primary endpoint was 5-year recurrence-free survival, and the secondary endpoint was 5-year cancer-specific survival.

TAKEAWAY:

• Among 723 patients followed for a median of 51 months, 683 had within-area tumors (mean age at CRC diagnosis, 51.8 years; 61.9% male) and 40 had outside-area tumors (mean age at CRC diagnosis, 61.1 years; 60.0% male).
• The within-area group had lower rate of 5-year recurrence-free survival than the outside-area group (75.1% vs 87.6%; P = .022), and lower rate of 5-year cancer-specific survival (81.1% vs 94.3%; P = .038).
• Within-area tumor location independently predicted worse recurrence-free survival (adjusted hazard ratio, 2.99; P = .030).
• In the within‑area group, higher MES was associated with stepwise (although nonsignificant) declines in recurrence‑free survival (inactive, 84.4%; mild-moderate, 79.4%; severe, 73.8%; P = .150). Corresponding cancer‑specific survival rates in these groups declined significantly (89.0%, 84.8%, and 73.8%, respectively; P = .048).

IN PRACTICE:

“These findings shift the clinical focus from inflammation as a risk factor for carcinogenesis to inflammation as a prognostic determinant, highlighting a potential new role for systematic endoscopic assessment of the background mucosa at cancer diagnosis,” the authors wrote.

SOURCE:

This study was led by Akiyoshi Ikebata, Department of Surgery, Keio University School of Medicine, Tokyo, Japan. It was published online in December 2025, in the Journal of Crohn's and Colitis.

LIMITATIONS:

The retrospective design introduced potential for unmeasured confounding and selection bias. The MES was assigned by local physicians without central review, which may have introduced variability. The small size of the outside‑area tumor group increased the risk for baseline imbalances.

DISCLOSURES:

No specific funding source was reported. The authors declared having no conflicts of interest.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.

A version of this article first appeared on Medscape.com.

TOPLINE:

Among patients with high-risk malignant colorectal polyps, 19% had residual disease, with rates of 25% in the immediate surgery group vs 9% in the nonoperative management group. The rate of rectum and sphincter preservation in the nonoperative surveillance group was over 90%, and all recurrences were successfully treated with salvage surgery or chemoradiotherapy.

METHODOLOGY:

• Although guidelines in the US recommend colorectal resection when a malignant colorectal polyp has high-risk features, some patients choose nonoperative management instead to avoid the associated averse effects and impact on quality of life. The safety of nonoperative management, however, remains unclear.
• A single-center cohort study conducted between 2015 and 2022 included 336 patients who underwent polypectomy in the colon (n = 226) or rectum (n = 110) and had at least one high-risk feature. High-risk features included positive margins, piecemeal resection with unclear margin, lymphovascular invasion, perineural invasion, poor differentiation, and tumor budding.
• The analysis compared rates of residual disease between those who had immediate surgery (62%) and nonoperative management (38%) following the removal of a malignant polyp, 15% of whom (n = 19) received systemic chemotherapy after polypectomy.
• Researchers also assessed the rates of distant metastasis between the two groups and the association between specific high-risk features and residual disease or post-treatment complications.

TAKEAWAY:

• In the overall population, 19% of patients had residual disease (63 of 336). Among the 208 patients who had immediate surgery, 25% (n = 51) had residual disease, including 9% (n = 19) with residual disease in the bowel wall and 19% (n = 39) in locoregional lymph nodes. Postoperative complications occurred in 12% of patients (n = 25) in the immediate surgery group, with 3% (n = 7) having complications considered grade 3 or higher.
• Among the 128 patients who received nonoperative surveillance, 9% (n = 12) developed recurrence during surveillance, 6% (n = 7) in the bowel wall and 4% (n = 5) in locoregional lymph nodes. All recurrences in the nonoperative surveillance group were successfully treated with either salvage surgery (n = 6) or chemoradiotherapy (n = 6).
• Among patients in the nonoperative group with a malignant polyp removed from the rectum, the rate of rectum preservation was 94% (74 of 79 patients); the sphincter preservation rate was 91% for tumors < 5 cm from the anal verge.
• Distant metastases occurred in 2% of all patients across both groups.

IN PRACTICE:

"The risk of residual disease after the removal of a malignant colorectal polyp with [high-risk features] is considerable, but nonoperative management offers the potential for organ preservation, with the availability of effective salvage options if rectal cancer is detected," the authors of the study concluded.

SOURCE:

The study, led by Thikhamporn Tawantanakorn, MD, and Martin R. Weiser, MD, of Memorial Sloan Kettering Cancer Center in New York City, was published online in JCO Oncology Advances.

LIMITATIONS:

The researchers noted several limitations, including variable follow-up among patients and challenges in assessing polypectomy histology, particularly after piecemeal resection, which limited evaluation of certain high-risk features such as tumor budding. Additionally, as the study was conducted at a specialized cancer center with dedicated gastrointestinal pathology and radiology services and readily available office endoscopy, the results may not be fully generalizable to less specialized centers.

DISCLOSURES:

Jinru Shia, MD, reported receiving consulting fees from Paige.AI and research funding through their institution. Andrea Cercek, MD, disclosed consulting roles with multiple pharmaceutical companies, including GlaxoSmithKline, Incyte, Merck, and others, as well as research funding from GlaxoSmithKline and Pfizer. Weiser reported receiving royalties as a section editor for UpToDate. Additional disclosures are noted in the original article.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.

A version of this article first appeared on Medscape.com.

TOPLINE:

Among patients with high-risk malignant colorectal polyps, 19% had residual disease, with rates of 25% in the immediate surgery group vs 9% in the nonoperative management group. The rate of rectum and sphincter preservation in the nonoperative surveillance group was over 90%, and all recurrences were successfully treated with salvage surgery or chemoradiotherapy.

METHODOLOGY:

• Although guidelines in the US recommend colorectal resection when a malignant colorectal polyp has high-risk features, some patients choose nonoperative management instead to avoid the associated averse effects and impact on quality of life. The safety of nonoperative management, however, remains unclear.
• A single-center cohort study conducted between 2015 and 2022 included 336 patients who underwent polypectomy in the colon (n = 226) or rectum (n = 110) and had at least one high-risk feature. High-risk features included positive margins, piecemeal resection with unclear margin, lymphovascular invasion, perineural invasion, poor differentiation, and tumor budding.
• The analysis compared rates of residual disease between those who had immediate surgery (62%) and nonoperative management (38%) following the removal of a malignant polyp, 15% of whom (n = 19) received systemic chemotherapy after polypectomy.
• Researchers also assessed the rates of distant metastasis between the two groups and the association between specific high-risk features and residual disease or post-treatment complications.

TAKEAWAY:

• In the overall population, 19% of patients had residual disease (63 of 336). Among the 208 patients who had immediate surgery, 25% (n = 51) had residual disease, including 9% (n = 19) with residual disease in the bowel wall and 19% (n = 39) in locoregional lymph nodes. Postoperative complications occurred in 12% of patients (n = 25) in the immediate surgery group, with 3% (n = 7) having complications considered grade 3 or higher.
• Among the 128 patients who received nonoperative surveillance, 9% (n = 12) developed recurrence during surveillance, 6% (n = 7) in the bowel wall and 4% (n = 5) in locoregional lymph nodes. All recurrences in the nonoperative surveillance group were successfully treated with either salvage surgery (n = 6) or chemoradiotherapy (n = 6).
• Among patients in the nonoperative group with a malignant polyp removed from the rectum, the rate of rectum preservation was 94% (74 of 79 patients); the sphincter preservation rate was 91% for tumors < 5 cm from the anal verge.
• Distant metastases occurred in 2% of all patients across both groups.

IN PRACTICE:

"The risk of residual disease after the removal of a malignant colorectal polyp with [high-risk features] is considerable, but nonoperative management offers the potential for organ preservation, with the availability of effective salvage options if rectal cancer is detected," the authors of the study concluded.

SOURCE:

The study, led by Thikhamporn Tawantanakorn, MD, and Martin R. Weiser, MD, of Memorial Sloan Kettering Cancer Center in New York City, was published online in JCO Oncology Advances.

LIMITATIONS:

The researchers noted several limitations, including variable follow-up among patients and challenges in assessing polypectomy histology, particularly after piecemeal resection, which limited evaluation of certain high-risk features such as tumor budding. Additionally, as the study was conducted at a specialized cancer center with dedicated gastrointestinal pathology and radiology services and readily available office endoscopy, the results may not be fully generalizable to less specialized centers.

DISCLOSURES:

Jinru Shia, MD, reported receiving consulting fees from Paige.AI and research funding through their institution. Andrea Cercek, MD, disclosed consulting roles with multiple pharmaceutical companies, including GlaxoSmithKline, Incyte, Merck, and others, as well as research funding from GlaxoSmithKline and Pfizer. Weiser reported receiving royalties as a section editor for UpToDate. Additional disclosures are noted in the original article.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.

A version of this article first appeared on Medscape.com.

TOPLINE:

Among patients with high-risk malignant colorectal polyps, 19% had residual disease, with rates of 25% in the immediate surgery group vs 9% in the nonoperative management group. The rate of rectum and sphincter preservation in the nonoperative surveillance group was over 90%, and all recurrences were successfully treated with salvage surgery or chemoradiotherapy.

METHODOLOGY:

• Although guidelines in the US recommend colorectal resection when a malignant colorectal polyp has high-risk features, some patients choose nonoperative management instead to avoid the associated averse effects and impact on quality of life. The safety of nonoperative management, however, remains unclear.
• A single-center cohort study conducted between 2015 and 2022 included 336 patients who underwent polypectomy in the colon (n = 226) or rectum (n = 110) and had at least one high-risk feature. High-risk features included positive margins, piecemeal resection with unclear margin, lymphovascular invasion, perineural invasion, poor differentiation, and tumor budding.
• The analysis compared rates of residual disease between those who had immediate surgery (62%) and nonoperative management (38%) following the removal of a malignant polyp, 15% of whom (n = 19) received systemic chemotherapy after polypectomy.
• Researchers also assessed the rates of distant metastasis between the two groups and the association between specific high-risk features and residual disease or post-treatment complications.

TAKEAWAY:

• In the overall population, 19% of patients had residual disease (63 of 336). Among the 208 patients who had immediate surgery, 25% (n = 51) had residual disease, including 9% (n = 19) with residual disease in the bowel wall and 19% (n = 39) in locoregional lymph nodes. Postoperative complications occurred in 12% of patients (n = 25) in the immediate surgery group, with 3% (n = 7) having complications considered grade 3 or higher.
• Among the 128 patients who received nonoperative surveillance, 9% (n = 12) developed recurrence during surveillance, 6% (n = 7) in the bowel wall and 4% (n = 5) in locoregional lymph nodes. All recurrences in the nonoperative surveillance group were successfully treated with either salvage surgery (n = 6) or chemoradiotherapy (n = 6).
• Among patients in the nonoperative group with a malignant polyp removed from the rectum, the rate of rectum preservation was 94% (74 of 79 patients); the sphincter preservation rate was 91% for tumors < 5 cm from the anal verge.
• Distant metastases occurred in 2% of all patients across both groups.

IN PRACTICE:

"The risk of residual disease after the removal of a malignant colorectal polyp with [high-risk features] is considerable, but nonoperative management offers the potential for organ preservation, with the availability of effective salvage options if rectal cancer is detected," the authors of the study concluded.

SOURCE:

The study, led by Thikhamporn Tawantanakorn, MD, and Martin R. Weiser, MD, of Memorial Sloan Kettering Cancer Center in New York City, was published online in JCO Oncology Advances.

LIMITATIONS:

The researchers noted several limitations, including variable follow-up among patients and challenges in assessing polypectomy histology, particularly after piecemeal resection, which limited evaluation of certain high-risk features such as tumor budding. Additionally, as the study was conducted at a specialized cancer center with dedicated gastrointestinal pathology and radiology services and readily available office endoscopy, the results may not be fully generalizable to less specialized centers.

DISCLOSURES:

Jinru Shia, MD, reported receiving consulting fees from Paige.AI and research funding through their institution. Andrea Cercek, MD, disclosed consulting roles with multiple pharmaceutical companies, including GlaxoSmithKline, Incyte, Merck, and others, as well as research funding from GlaxoSmithKline and Pfizer. Weiser reported receiving royalties as a section editor for UpToDate. Additional disclosures are noted in the original article.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.

A version of this article first appeared on Medscape.com.

Intensive long-distance running could be a risk for advanced adenomas (AAs) for the colon, a small prospective study reported this summer at the American Society of Clinical Oncology (ASCO) 2025.

Refined screening strategies for this running population are therefore warranted, and pathologic and epidemiologic evaluations should explore causation and ancillary risk factors in this unique population, according to Timothy L. Cannon, MD, oncologist at Inova Schar Cancer Institute in Fairfax, Virginia, and colleagues.

The full study (NCT 05419531), which is currently being reviewed for publication, looked at colonoscopy results from 100 marathon and ultramarathon runners and found that almost half had polyps, and 15% (95% CI, 7.9-22.4) had confirmed AAs).

The AA rate was higher than the 4.5% to 6% seen in adults in their late 40s in the general population and was higher even than the 12% found in Alaska Natives, who are at heightened risk for colon cancer.

"After meeting 3 extreme endurance athletes — 2 who ran 100-mile ultramarathons and 1 lady who ran dozens of triathlons — with stage IV colon cancer before age 40, I began to be suspicious of a link," Cannon told Medscape Medical News. At least 2 of them said they were told that bleeding after long runs was common, which they took to mean as normal. "I could imagine multiple reasons that endurance runners would be predisposed to cancer, with my initial focus on the inflammation and cell turnover incited by the well-described ischemia and runner's colitis."

Study Details

From October 2022 to December 2024, 100 eligible participants aged 35 to 50 years had colonoscopies. The median age was 42.5 years; 55 participants were female and 45 were male. In terms of endurance eligibility, all had completed at ≥ 2 registered ultramarathons (50 km or longer) or 5 registered marathons (26.2 miles). Patients were excluded if they were known or suspected to have inflammatory bowel disease, familial adenomatous polyposis, or Lynch syndrome (hereditary nonpolyposis colorectal cancer).

The historical 1.2% in average-risk individuals aged 40-49 years was used for the expected rate of AAs, defined as lesions > 10 mm, lesions with 25% tubulovillous features, or high-grade dysplasia.

In other findings, 39 had ≥ 1 adenoma and had ≥ 3 adenomas but did not meet AA criteria and were not included in the 15% with AA.

While no colon cancer was detected in the cohort, Cannon said 30% experienced rectal bleeding after exercise, especially those with AAs compared with those without: 53% vs 22%. "While rectal bleeding had a significant association with finding advanced adenomas on the colonoscopy, there were still many with advanced adenomas who reported no bleeding," he said.

Runner's colitis, or trots, is a common condition thought to be related to ischemia, mechanical stress, or adverse impact on the gut microbiome. "Mechanism is the huge question that I certainly can't answer at this point," Cannon said. "At some distance, blood flow gets diverted from the splanchnic circulation to the legs, and gut ischemia seems to ensue. I envision high rates of disorderly cell turnover and more opportunities for mutagenesis. This needs to be studied, and what I am describing is certainly either an oversimplification or simply not related at all."

The authors noted that exercise-induced gastrointestinal injury is likely associated with reduced blood flow to the intestines during long-distance running, but not evidence has linked this bowel ischemia to carcinogenesis.

Diet could be another factor. "I am fascinated with runners' diets. They seem to consume, on average, a huge amount of ultraprocessed bars and goos. They also may drink from plastic bottles far more than the average person. These are just 2 of many possibilities," Cannon said. "Nearly a third of our participants were vegan or vegetarian. We are planning a second, more detailed, survey or our participants. We will really dig down on these questions as well as specifics regarding their training regimens."

Commenting on the study but not involved in it, Thomas F. Imperiale, MD, professor of gastroenterology and hepatology at Indiana University Indianapolis, said that while the findings are provocative, several methodological issues require consideration in subsequent research.

"First, the comparative benchmark of advanced adenoma prevalence of 1.2% is based on screening colonoscopy data from 25 years ago. At the very least, a concurrent benchmark should be used," he told Medscape Medical News. The second issue is the absence of a control group of persons who may exercise but who do not run marathons. "This addition would strengthen study validity more than using a concurrent comparison."

The case group of long-distance runners and a control group of nonmarathon runners could be compared for prevalence of AAs with adjustment for age, sex, race or ethnicity, family history of colorectal cancer, diet, other physical activity, tobacco use history, BMI or waist circumference, ethanol use, and perhaps other early-life exposures and indication for colonoscopy. "Last, it would be interesting to know whether and how often the 100 participants developed symptoms possibly consistent with colonic ischemia either during or after long-distance runs, which might provide indirect support for the presumptive mechanism of action."

In other comments, Hamed Khalili, MD, MPH, gastroenterologist at Massachusetts General Hospital and associate professor at Harvard Medical School, both in Boston, called the results very preliminary. "The sample size is small, and the comparator group is a historical control, so it's unclear whether the observed differences are just a sampling issue," he said.

Cannon has this advice for physicians: "Please don't dismiss symptoms of runner's colitis as benign. This condition requires investigation," he said. While he hasn't seen any expert recommendation to treat postrunning bleeding any differently from other causes of melena or hematochezia, both of which would normally merit a colonoscopy, in practice many gastroenterologists dismiss this type of bleeding as benign. "If larger studies confirm our findings, I don't think it's out of the question that marathoners will have unique screening recommendations. But this study is not robust enough, of course, to merit such a recommendation."

His group is planning a study on the runner's microbiome and on the proteome of the colonic tissue in this group.

Cannon reported having no relevant conflicts of interest to disclose. Imperiale and Khalili reported having no conflicts of interest relevant to their comments on the study.

A version of this article first appeared on Medscape.com.

Intensive long-distance running could be a risk for advanced adenomas (AAs) for the colon, a small prospective study reported this summer at the American Society of Clinical Oncology (ASCO) 2025.

Refined screening strategies for this running population are therefore warranted, and pathologic and epidemiologic evaluations should explore causation and ancillary risk factors in this unique population, according to Timothy L. Cannon, MD, oncologist at Inova Schar Cancer Institute in Fairfax, Virginia, and colleagues.

The full study (NCT 05419531), which is currently being reviewed for publication, looked at colonoscopy results from 100 marathon and ultramarathon runners and found that almost half had polyps, and 15% (95% CI, 7.9-22.4) had confirmed AAs).

The AA rate was higher than the 4.5% to 6% seen in adults in their late 40s in the general population and was higher even than the 12% found in Alaska Natives, who are at heightened risk for colon cancer.

"After meeting 3 extreme endurance athletes — 2 who ran 100-mile ultramarathons and 1 lady who ran dozens of triathlons — with stage IV colon cancer before age 40, I began to be suspicious of a link," Cannon told Medscape Medical News. At least 2 of them said they were told that bleeding after long runs was common, which they took to mean as normal. "I could imagine multiple reasons that endurance runners would be predisposed to cancer, with my initial focus on the inflammation and cell turnover incited by the well-described ischemia and runner's colitis."

Study Details

From October 2022 to December 2024, 100 eligible participants aged 35 to 50 years had colonoscopies. The median age was 42.5 years; 55 participants were female and 45 were male. In terms of endurance eligibility, all had completed at ≥ 2 registered ultramarathons (50 km or longer) or 5 registered marathons (26.2 miles). Patients were excluded if they were known or suspected to have inflammatory bowel disease, familial adenomatous polyposis, or Lynch syndrome (hereditary nonpolyposis colorectal cancer).

The historical 1.2% in average-risk individuals aged 40-49 years was used for the expected rate of AAs, defined as lesions > 10 mm, lesions with 25% tubulovillous features, or high-grade dysplasia.

In other findings, 39 had ≥ 1 adenoma and had ≥ 3 adenomas but did not meet AA criteria and were not included in the 15% with AA.

While no colon cancer was detected in the cohort, Cannon said 30% experienced rectal bleeding after exercise, especially those with AAs compared with those without: 53% vs 22%. "While rectal bleeding had a significant association with finding advanced adenomas on the colonoscopy, there were still many with advanced adenomas who reported no bleeding," he said.

Runner's colitis, or trots, is a common condition thought to be related to ischemia, mechanical stress, or adverse impact on the gut microbiome. "Mechanism is the huge question that I certainly can't answer at this point," Cannon said. "At some distance, blood flow gets diverted from the splanchnic circulation to the legs, and gut ischemia seems to ensue. I envision high rates of disorderly cell turnover and more opportunities for mutagenesis. This needs to be studied, and what I am describing is certainly either an oversimplification or simply not related at all."

The authors noted that exercise-induced gastrointestinal injury is likely associated with reduced blood flow to the intestines during long-distance running, but not evidence has linked this bowel ischemia to carcinogenesis.

Diet could be another factor. "I am fascinated with runners' diets. They seem to consume, on average, a huge amount of ultraprocessed bars and goos. They also may drink from plastic bottles far more than the average person. These are just 2 of many possibilities," Cannon said. "Nearly a third of our participants were vegan or vegetarian. We are planning a second, more detailed, survey or our participants. We will really dig down on these questions as well as specifics regarding their training regimens."

Commenting on the study but not involved in it, Thomas F. Imperiale, MD, professor of gastroenterology and hepatology at Indiana University Indianapolis, said that while the findings are provocative, several methodological issues require consideration in subsequent research.

"First, the comparative benchmark of advanced adenoma prevalence of 1.2% is based on screening colonoscopy data from 25 years ago. At the very least, a concurrent benchmark should be used," he told Medscape Medical News. The second issue is the absence of a control group of persons who may exercise but who do not run marathons. "This addition would strengthen study validity more than using a concurrent comparison."

The case group of long-distance runners and a control group of nonmarathon runners could be compared for prevalence of AAs with adjustment for age, sex, race or ethnicity, family history of colorectal cancer, diet, other physical activity, tobacco use history, BMI or waist circumference, ethanol use, and perhaps other early-life exposures and indication for colonoscopy. "Last, it would be interesting to know whether and how often the 100 participants developed symptoms possibly consistent with colonic ischemia either during or after long-distance runs, which might provide indirect support for the presumptive mechanism of action."

In other comments, Hamed Khalili, MD, MPH, gastroenterologist at Massachusetts General Hospital and associate professor at Harvard Medical School, both in Boston, called the results very preliminary. "The sample size is small, and the comparator group is a historical control, so it's unclear whether the observed differences are just a sampling issue," he said.

Cannon has this advice for physicians: "Please don't dismiss symptoms of runner's colitis as benign. This condition requires investigation," he said. While he hasn't seen any expert recommendation to treat postrunning bleeding any differently from other causes of melena or hematochezia, both of which would normally merit a colonoscopy, in practice many gastroenterologists dismiss this type of bleeding as benign. "If larger studies confirm our findings, I don't think it's out of the question that marathoners will have unique screening recommendations. But this study is not robust enough, of course, to merit such a recommendation."

His group is planning a study on the runner's microbiome and on the proteome of the colonic tissue in this group.

Cannon reported having no relevant conflicts of interest to disclose. Imperiale and Khalili reported having no conflicts of interest relevant to their comments on the study.

A version of this article first appeared on Medscape.com.

Intensive long-distance running could be a risk for advanced adenomas (AAs) for the colon, a small prospective study reported this summer at the American Society of Clinical Oncology (ASCO) 2025.

Refined screening strategies for this running population are therefore warranted, and pathologic and epidemiologic evaluations should explore causation and ancillary risk factors in this unique population, according to Timothy L. Cannon, MD, oncologist at Inova Schar Cancer Institute in Fairfax, Virginia, and colleagues.

The full study (NCT 05419531), which is currently being reviewed for publication, looked at colonoscopy results from 100 marathon and ultramarathon runners and found that almost half had polyps, and 15% (95% CI, 7.9-22.4) had confirmed AAs).

The AA rate was higher than the 4.5% to 6% seen in adults in their late 40s in the general population and was higher even than the 12% found in Alaska Natives, who are at heightened risk for colon cancer.

"After meeting 3 extreme endurance athletes — 2 who ran 100-mile ultramarathons and 1 lady who ran dozens of triathlons — with stage IV colon cancer before age 40, I began to be suspicious of a link," Cannon told Medscape Medical News. At least 2 of them said they were told that bleeding after long runs was common, which they took to mean as normal. "I could imagine multiple reasons that endurance runners would be predisposed to cancer, with my initial focus on the inflammation and cell turnover incited by the well-described ischemia and runner's colitis."

Study Details

From October 2022 to December 2024, 100 eligible participants aged 35 to 50 years had colonoscopies. The median age was 42.5 years; 55 participants were female and 45 were male. In terms of endurance eligibility, all had completed at ≥ 2 registered ultramarathons (50 km or longer) or 5 registered marathons (26.2 miles). Patients were excluded if they were known or suspected to have inflammatory bowel disease, familial adenomatous polyposis, or Lynch syndrome (hereditary nonpolyposis colorectal cancer).

The historical 1.2% in average-risk individuals aged 40-49 years was used for the expected rate of AAs, defined as lesions > 10 mm, lesions with 25% tubulovillous features, or high-grade dysplasia.

In other findings, 39 had ≥ 1 adenoma and had ≥ 3 adenomas but did not meet AA criteria and were not included in the 15% with AA.

While no colon cancer was detected in the cohort, Cannon said 30% experienced rectal bleeding after exercise, especially those with AAs compared with those without: 53% vs 22%. "While rectal bleeding had a significant association with finding advanced adenomas on the colonoscopy, there were still many with advanced adenomas who reported no bleeding," he said.

Runner's colitis, or trots, is a common condition thought to be related to ischemia, mechanical stress, or adverse impact on the gut microbiome. "Mechanism is the huge question that I certainly can't answer at this point," Cannon said. "At some distance, blood flow gets diverted from the splanchnic circulation to the legs, and gut ischemia seems to ensue. I envision high rates of disorderly cell turnover and more opportunities for mutagenesis. This needs to be studied, and what I am describing is certainly either an oversimplification or simply not related at all."

The authors noted that exercise-induced gastrointestinal injury is likely associated with reduced blood flow to the intestines during long-distance running, but not evidence has linked this bowel ischemia to carcinogenesis.

Diet could be another factor. "I am fascinated with runners' diets. They seem to consume, on average, a huge amount of ultraprocessed bars and goos. They also may drink from plastic bottles far more than the average person. These are just 2 of many possibilities," Cannon said. "Nearly a third of our participants were vegan or vegetarian. We are planning a second, more detailed, survey or our participants. We will really dig down on these questions as well as specifics regarding their training regimens."

Commenting on the study but not involved in it, Thomas F. Imperiale, MD, professor of gastroenterology and hepatology at Indiana University Indianapolis, said that while the findings are provocative, several methodological issues require consideration in subsequent research.

"First, the comparative benchmark of advanced adenoma prevalence of 1.2% is based on screening colonoscopy data from 25 years ago. At the very least, a concurrent benchmark should be used," he told Medscape Medical News. The second issue is the absence of a control group of persons who may exercise but who do not run marathons. "This addition would strengthen study validity more than using a concurrent comparison."

The case group of long-distance runners and a control group of nonmarathon runners could be compared for prevalence of AAs with adjustment for age, sex, race or ethnicity, family history of colorectal cancer, diet, other physical activity, tobacco use history, BMI or waist circumference, ethanol use, and perhaps other early-life exposures and indication for colonoscopy. "Last, it would be interesting to know whether and how often the 100 participants developed symptoms possibly consistent with colonic ischemia either during or after long-distance runs, which might provide indirect support for the presumptive mechanism of action."

In other comments, Hamed Khalili, MD, MPH, gastroenterologist at Massachusetts General Hospital and associate professor at Harvard Medical School, both in Boston, called the results very preliminary. "The sample size is small, and the comparator group is a historical control, so it's unclear whether the observed differences are just a sampling issue," he said.

Cannon has this advice for physicians: "Please don't dismiss symptoms of runner's colitis as benign. This condition requires investigation," he said. While he hasn't seen any expert recommendation to treat postrunning bleeding any differently from other causes of melena or hematochezia, both of which would normally merit a colonoscopy, in practice many gastroenterologists dismiss this type of bleeding as benign. "If larger studies confirm our findings, I don't think it's out of the question that marathoners will have unique screening recommendations. But this study is not robust enough, of course, to merit such a recommendation."

His group is planning a study on the runner's microbiome and on the proteome of the colonic tissue in this group.

Cannon reported having no relevant conflicts of interest to disclose. Imperiale and Khalili reported having no conflicts of interest relevant to their comments on the study.

A version of this article first appeared on Medscape.com.

TOPLINE: A novel single-incision robotic surgery technique for colorectal procedures demonstrated feasibility with 0% conversion to open surgery rate; only 1 case required additional ports. The technique achieved a 30-day all-severity morbidity rate of 20% and major morbidity of 6%.

METHODOLOGY: 

• Researchers conducted a retrospective review to report a unique, single-incision robotic surgery technique that uses a fascial wound protector device and multiport robotic surgical system in colorectal surgery.
• Analysis included 50 patients (60% women) with mean ages of 53.5 years and median BMI of 27.2 kg/m².
• Study was performed at a single quaternary, urban, academic institution from December 2023 to April 2025.
• Patients aged ≥ 18 years with colorectal indications who underwent robotic single-incision surgery using a Da Vinci multiport robotic platform were included.

TAKEAWAY:

• Conversion to open surgery rate was 0%; 1 case required additional robotic ports.
• The 30-day all-severity morbidity rate was 20%; 30-day major morbidity was 6%.
• Pathologies treated included Crohn's disease (26%), diverticulitis (22%), colon cancer (16%), colostomy status (8%), and rectal cancer (4%).
• Successful procedures included right-sided colectomies (14%), left-sided colectomies (28%), total colectomy (4%), rectal resection (4%), small bowel procedures (22%), and ostomy creation/reversal (18%).

IN PRACTICE: "Our rSIS technique utilizing a multiport robotic system is safe and feasible across a wide spectrum of colorectal procedures," wrote the study authors.

LIMITATIONS: According to the authors, reproducible successful completion of surgeries using this technique may be challenging in populations requiring deep pelvic dissections, especially in narrow male pelvis cases, and in patients with very high BMI and significant intra-abdominal adipose tissue.

DISCLOSURES: The authors report no financial support was received for this study and declare no competing interests.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.

TOPLINE: A novel single-incision robotic surgery technique for colorectal procedures demonstrated feasibility with 0% conversion to open surgery rate; only 1 case required additional ports. The technique achieved a 30-day all-severity morbidity rate of 20% and major morbidity of 6%.

METHODOLOGY: 

• Researchers conducted a retrospective review to report a unique, single-incision robotic surgery technique that uses a fascial wound protector device and multiport robotic surgical system in colorectal surgery.
• Analysis included 50 patients (60% women) with mean ages of 53.5 years and median BMI of 27.2 kg/m².
• Study was performed at a single quaternary, urban, academic institution from December 2023 to April 2025.
• Patients aged ≥ 18 years with colorectal indications who underwent robotic single-incision surgery using a Da Vinci multiport robotic platform were included.

TAKEAWAY:

• Conversion to open surgery rate was 0%; 1 case required additional robotic ports.
• The 30-day all-severity morbidity rate was 20%; 30-day major morbidity was 6%.
• Pathologies treated included Crohn's disease (26%), diverticulitis (22%), colon cancer (16%), colostomy status (8%), and rectal cancer (4%).
• Successful procedures included right-sided colectomies (14%), left-sided colectomies (28%), total colectomy (4%), rectal resection (4%), small bowel procedures (22%), and ostomy creation/reversal (18%).

IN PRACTICE: "Our rSIS technique utilizing a multiport robotic system is safe and feasible across a wide spectrum of colorectal procedures," wrote the study authors.

LIMITATIONS: According to the authors, reproducible successful completion of surgeries using this technique may be challenging in populations requiring deep pelvic dissections, especially in narrow male pelvis cases, and in patients with very high BMI and significant intra-abdominal adipose tissue.

DISCLOSURES: The authors report no financial support was received for this study and declare no competing interests.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.

TOPLINE: A novel single-incision robotic surgery technique for colorectal procedures demonstrated feasibility with 0% conversion to open surgery rate; only 1 case required additional ports. The technique achieved a 30-day all-severity morbidity rate of 20% and major morbidity of 6%.

METHODOLOGY: 

• Researchers conducted a retrospective review to report a unique, single-incision robotic surgery technique that uses a fascial wound protector device and multiport robotic surgical system in colorectal surgery.
• Analysis included 50 patients (60% women) with mean ages of 53.5 years and median BMI of 27.2 kg/m².
• Study was performed at a single quaternary, urban, academic institution from December 2023 to April 2025.
• Patients aged ≥ 18 years with colorectal indications who underwent robotic single-incision surgery using a Da Vinci multiport robotic platform were included.

TAKEAWAY:

• Conversion to open surgery rate was 0%; 1 case required additional robotic ports.
• The 30-day all-severity morbidity rate was 20%; 30-day major morbidity was 6%.
• Pathologies treated included Crohn's disease (26%), diverticulitis (22%), colon cancer (16%), colostomy status (8%), and rectal cancer (4%).
• Successful procedures included right-sided colectomies (14%), left-sided colectomies (28%), total colectomy (4%), rectal resection (4%), small bowel procedures (22%), and ostomy creation/reversal (18%).

IN PRACTICE: "Our rSIS technique utilizing a multiport robotic system is safe and feasible across a wide spectrum of colorectal procedures," wrote the study authors.

LIMITATIONS: According to the authors, reproducible successful completion of surgeries using this technique may be challenging in populations requiring deep pelvic dissections, especially in narrow male pelvis cases, and in patients with very high BMI and significant intra-abdominal adipose tissue.

DISCLOSURES: The authors report no financial support was received for this study and declare no competing interests.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.

TOPLINE: Large Language Models (LLMs) achieve more than 95% accuracy in extracting colorectal cancer and dysplasia diagnoses from Veterans Health Administration (VHA) pathology reports, including patients with Million Veteran Program (MVP) genomic data. The validated approach using publicly available LLMs demonstrates excellent performance across both Inflammatory Bowel Disease (IBD) and non-IBD populations.

METHODOLOGY: 

Researchers analyzed 116,373 pathology reports generated in the VHA between 1999 and 2024, utilizing search term filtering followed by simple yes/no question prompts for identifying colorectal dysplasia, high-grade dysplasia and/or colorectal adenocarcinoma, and invasive colorectal cancer.

• Results were compared to blinded manual chart review of 200 to 300 pathology reports for each patient cohort and diagnostic task, totaling 3,816 reviewed reports, to validate the LLM approach.

• Validation was performed independently in IBD and non-IBD populations using Gemma-2 and Llama-3 LLMs without any task-specific training or fine-tuning.

• Performance metrics included F1 scores, positive predictive value, negative predictive value, sensitivity, specificity, and Matthew's correlation coefficient to evaluate accuracy across different tasks.

TAKEAWAY:

• In patients with IBD in the MVP, the LLM achieved (F1-score, 96.9%; 95% confidence interval [CI], 94.0%-99.6%) for identifying dysplasia, (F1-score, 93.7%; 95% CI, 88.2%-98.4%) for identifying high-grade dysplasia/colorectal cancer, and (F1-score, 98%; 95% CI, 96.3%-99.4%) for identifying colorectal cancer.

• In non-IBD MVP patients, the LLM demonstrated (F1-score, 99.2%; 95% CI, 98.2%-100%) for identifying colorectal dysplasia, (F1-score, 96.5%; 95% CI, 93.0%-99.2%) for high-grade dysplasia/colorectal cancer, and (F1-score, 95%; 95% CI, 92.8%-97.2%) for identifying colorectal cancer.

• Agreement between reviewers was excellent across tasks, with (Cohen's kappa, 89%-97%) for main tasks, and (Cohen's kappa, 78.1%-93.1%) for indefinite for dysplasia in IBD cohort.

• The LLM approach maintained high accuracy when applied to full pathology reports, with (F1-score, 97.1%; 95% CI, 93.5%-100%) for dysplasia detection in IBD patients.

IN PRACTICE: “We have shown that LLMs are powerful, potentially generalizable tools for accurately extracting important information from clinical semistructured and unstructured text and which require little human-led development.” the authors of the study wrote

SOURCE: The study was based on data from the Million Veteran Program and supported by the Office of Research and Development, Veterans Health Administration, and the US Department of Veterans Affairs Biomedical Laboratory. It was published online in BMJ Open Gastroenterology.

LIMITATIONS:  According to the authors, this research may be specific to the VHA system and the LLM models used. The authors did not test larger models. The authors acknowledge that without long-term access to graphics processing units, they could not feasibly test larger models, which may overcome some of the shortcomings seen in smaller models. Additionally, the researchers could not rule out overlap between Million Veteran Program and Corporate Data Warehouse reports, though they state that results in either cohort alone are sufficient validation compared with previously published work.

DISCLOSURES: The study was supported by Merit Review Award from the United States Department of Veterans Affairs Biomedical Laboratory Research and Development Service, AGA Research Foundation, National Institutes of Health grants, and the National Library of Medicine Training Grant. Kit Curtius reported receiving an investigator-led research grant from Phathom Pharmaceuticals. Shailja C Shah disclosed being a paid consultant for RedHill Biopharma and Phathom Pharmaceuticals, and an unpaid scientific advisory board member for Ilico Genetics, Inc.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.

TOPLINE: Large Language Models (LLMs) achieve more than 95% accuracy in extracting colorectal cancer and dysplasia diagnoses from Veterans Health Administration (VHA) pathology reports, including patients with Million Veteran Program (MVP) genomic data. The validated approach using publicly available LLMs demonstrates excellent performance across both Inflammatory Bowel Disease (IBD) and non-IBD populations.

METHODOLOGY: 

Researchers analyzed 116,373 pathology reports generated in the VHA between 1999 and 2024, utilizing search term filtering followed by simple yes/no question prompts for identifying colorectal dysplasia, high-grade dysplasia and/or colorectal adenocarcinoma, and invasive colorectal cancer.

• Results were compared to blinded manual chart review of 200 to 300 pathology reports for each patient cohort and diagnostic task, totaling 3,816 reviewed reports, to validate the LLM approach.

• Validation was performed independently in IBD and non-IBD populations using Gemma-2 and Llama-3 LLMs without any task-specific training or fine-tuning.

• Performance metrics included F1 scores, positive predictive value, negative predictive value, sensitivity, specificity, and Matthew's correlation coefficient to evaluate accuracy across different tasks.

TAKEAWAY:

• In patients with IBD in the MVP, the LLM achieved (F1-score, 96.9%; 95% confidence interval [CI], 94.0%-99.6%) for identifying dysplasia, (F1-score, 93.7%; 95% CI, 88.2%-98.4%) for identifying high-grade dysplasia/colorectal cancer, and (F1-score, 98%; 95% CI, 96.3%-99.4%) for identifying colorectal cancer.

• In non-IBD MVP patients, the LLM demonstrated (F1-score, 99.2%; 95% CI, 98.2%-100%) for identifying colorectal dysplasia, (F1-score, 96.5%; 95% CI, 93.0%-99.2%) for high-grade dysplasia/colorectal cancer, and (F1-score, 95%; 95% CI, 92.8%-97.2%) for identifying colorectal cancer.

• Agreement between reviewers was excellent across tasks, with (Cohen's kappa, 89%-97%) for main tasks, and (Cohen's kappa, 78.1%-93.1%) for indefinite for dysplasia in IBD cohort.

• The LLM approach maintained high accuracy when applied to full pathology reports, with (F1-score, 97.1%; 95% CI, 93.5%-100%) for dysplasia detection in IBD patients.

IN PRACTICE: “We have shown that LLMs are powerful, potentially generalizable tools for accurately extracting important information from clinical semistructured and unstructured text and which require little human-led development.” the authors of the study wrote

SOURCE: The study was based on data from the Million Veteran Program and supported by the Office of Research and Development, Veterans Health Administration, and the US Department of Veterans Affairs Biomedical Laboratory. It was published online in BMJ Open Gastroenterology.

LIMITATIONS:  According to the authors, this research may be specific to the VHA system and the LLM models used. The authors did not test larger models. The authors acknowledge that without long-term access to graphics processing units, they could not feasibly test larger models, which may overcome some of the shortcomings seen in smaller models. Additionally, the researchers could not rule out overlap between Million Veteran Program and Corporate Data Warehouse reports, though they state that results in either cohort alone are sufficient validation compared with previously published work.

DISCLOSURES: The study was supported by Merit Review Award from the United States Department of Veterans Affairs Biomedical Laboratory Research and Development Service, AGA Research Foundation, National Institutes of Health grants, and the National Library of Medicine Training Grant. Kit Curtius reported receiving an investigator-led research grant from Phathom Pharmaceuticals. Shailja C Shah disclosed being a paid consultant for RedHill Biopharma and Phathom Pharmaceuticals, and an unpaid scientific advisory board member for Ilico Genetics, Inc.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.

TOPLINE: Large Language Models (LLMs) achieve more than 95% accuracy in extracting colorectal cancer and dysplasia diagnoses from Veterans Health Administration (VHA) pathology reports, including patients with Million Veteran Program (MVP) genomic data. The validated approach using publicly available LLMs demonstrates excellent performance across both Inflammatory Bowel Disease (IBD) and non-IBD populations.

METHODOLOGY: 

Researchers analyzed 116,373 pathology reports generated in the VHA between 1999 and 2024, utilizing search term filtering followed by simple yes/no question prompts for identifying colorectal dysplasia, high-grade dysplasia and/or colorectal adenocarcinoma, and invasive colorectal cancer.

• Results were compared to blinded manual chart review of 200 to 300 pathology reports for each patient cohort and diagnostic task, totaling 3,816 reviewed reports, to validate the LLM approach.

• Validation was performed independently in IBD and non-IBD populations using Gemma-2 and Llama-3 LLMs without any task-specific training or fine-tuning.

• Performance metrics included F1 scores, positive predictive value, negative predictive value, sensitivity, specificity, and Matthew's correlation coefficient to evaluate accuracy across different tasks.

TAKEAWAY:

• In patients with IBD in the MVP, the LLM achieved (F1-score, 96.9%; 95% confidence interval [CI], 94.0%-99.6%) for identifying dysplasia, (F1-score, 93.7%; 95% CI, 88.2%-98.4%) for identifying high-grade dysplasia/colorectal cancer, and (F1-score, 98%; 95% CI, 96.3%-99.4%) for identifying colorectal cancer.

• In non-IBD MVP patients, the LLM demonstrated (F1-score, 99.2%; 95% CI, 98.2%-100%) for identifying colorectal dysplasia, (F1-score, 96.5%; 95% CI, 93.0%-99.2%) for high-grade dysplasia/colorectal cancer, and (F1-score, 95%; 95% CI, 92.8%-97.2%) for identifying colorectal cancer.

• Agreement between reviewers was excellent across tasks, with (Cohen's kappa, 89%-97%) for main tasks, and (Cohen's kappa, 78.1%-93.1%) for indefinite for dysplasia in IBD cohort.

• The LLM approach maintained high accuracy when applied to full pathology reports, with (F1-score, 97.1%; 95% CI, 93.5%-100%) for dysplasia detection in IBD patients.

IN PRACTICE: “We have shown that LLMs are powerful, potentially generalizable tools for accurately extracting important information from clinical semistructured and unstructured text and which require little human-led development.” the authors of the study wrote

SOURCE: The study was based on data from the Million Veteran Program and supported by the Office of Research and Development, Veterans Health Administration, and the US Department of Veterans Affairs Biomedical Laboratory. It was published online in BMJ Open Gastroenterology.

LIMITATIONS:  According to the authors, this research may be specific to the VHA system and the LLM models used. The authors did not test larger models. The authors acknowledge that without long-term access to graphics processing units, they could not feasibly test larger models, which may overcome some of the shortcomings seen in smaller models. Additionally, the researchers could not rule out overlap between Million Veteran Program and Corporate Data Warehouse reports, though they state that results in either cohort alone are sufficient validation compared with previously published work.

DISCLOSURES: The study was supported by Merit Review Award from the United States Department of Veterans Affairs Biomedical Laboratory Research and Development Service, AGA Research Foundation, National Institutes of Health grants, and the National Library of Medicine Training Grant. Kit Curtius reported receiving an investigator-led research grant from Phathom Pharmaceuticals. Shailja C Shah disclosed being a paid consultant for RedHill Biopharma and Phathom Pharmaceuticals, and an unpaid scientific advisory board member for Ilico Genetics, Inc.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.

BERLIN — Re-treatment with an antiepidermal growth factor receptor (EGFR) agent is effective in patients with chemorefractory metastatic colorectal cancer (mCRC) with RAS and BRAF wild-type tumors confirmed on circulating tumor DNA (ctDNA), although the sequencing of therapy does not seem to matter, suggest overall survival results from the crossover trial PARERE.

The findings nevertheless indicate that anti-EGFR rechallenge with panitumumab may prolong progression-free survival (PFS) over the multiple kinase inhibitor regorafenib. This suggests that “the most pragmatic choice” would be to give the anti-EGFR before regorafenib, said study presenter Marco Maria Germani, MD, Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy.

The caveat, however, is in patients who have an anti-EGFR interval since previously receiving the drugs of < 6 months. Those patients appeared to do better if they had regorafenib first and then anti-EGFR rechallenge.

Overall, Germani said that “since [trifluridine/tipiracil] plus bevacizumab is today the third-line standard of care” in this patient population, “anti-EGFR re-treatment might be considered after progression” on that combination.

Germani presented the research on October 18 at the European Society for Medical Oncology (ESMO) Annual Meeting 2025, which was simultaneously published in the Annals of Oncology.

Michel P. Ducreux, MD, PhD, head of the Digestive Cancer Committee at Gustave Roussy, Villejuif, France, and invited discussant for the results, said, despite the study being negative, it is “very important to continue to perform this kind of trial to evaluate the [ideal] sequence in the treatment of our patients.”

He continued that the secondary endpoints in the trial of PFS and objective response and disease control rates were “fairly in favor of the use of rechallenge before regorafenib, and in my opinion, this is really quite convincing.”

Ducreux, who was not involved in PARERE trail, also pointed to the sex difference seen in the study, which suggested that women responded much better to having anti-EGFR retreatment before regorafenib than did men.

Similar findings have been reported in a number of other trials, and previous work has suggested that there are sex differences in the pharmacokinetics of several anticancer drugs. However, while this is “very important,” he said that “we never consider it, because we are not able to really explain [it].”

Overall, he concluded that, on the basis of these results, he would agree with the notion that it is better to propose a rechallenge with anti-EGFR treatment as the fourth-line therapy in this patient population, before administering regorafenib.

Ducreux explained that, after a partial response, tumors acquire resistance to EGFR inhibitors through alterations and mutations that occur during treatment, via nongenetic mechanisms, and through treatment-induced selection for preexisting mutations.

Previous work has shown that mutations, such as in the RAS gene, are detectable early during EGFR inhibitor therapy, but that they then decay exponentially once the drugs are stopped, with the potential that tumors regain their sensitivity to them.

Germani said that this means that ctDNA-guided retreatment with anti-EGFR therapies is a “promising approach” in pretreated patients with RAS and BRAF wild-type mCRC, and that the sequencing of the drugs may be important. Indeed, the REVERCE trial showed that giving regorafenib followed by the anti-EGFR drug cetuzximab was associated with longer overall survival than the other way around in anti-EGFR medication-naive patients.

 

Methods and Results

For PARERE, the researchers enrolled patients aged at least 18 years with RAS and BRAF wild-type mCRC who were previously treated with a first-line anti-EGFR-containing regimen and had at least a partial response or stable disease for at least 6 months.

The patients were also required to have had at least one intervening anti-EGFR-free line of therapy, and to have previously received treatment with fluoropyrimidine, oxaliplatin, irinotecan, and anti-angiogenics. At least 4 months were required to have passed between the end of anti-EGFR administration and screening for the study.

In all, 428 patients were screened between December 2020 and December 2024, with 213 patients with RAS and BRAF wild-type mCRC, as detected on ctDNA, enrolled. They were randomized to panitumumab or regorafenib until first progression, followed by regorafenib, if they started on panitumumab, or panitumumab, if they started on regorafenib, until second progression.

The median age of the patients was 61 years among those who started on panitumumab and 64 years among those initially given regorafenib in the trial, and 63% and 57%, respectively, were male. The median number of prior lines of therapy was two in both groups, and 65% and 69%, respectively, had received pantitumumab as their first-line anti-EGFR.

Initial findings from the study presented at the 2025 ASCO Annual Meeting indicated that, after a median follow-up of 23.5 months, there was no significant difference in the median first PFS between the two treatment arms.

However, patients who started with panitumumab had a significant improvement in both the objective response and disease control rates (P < .001), as well as a signal for a potentially longer median second PFS, than those who started with regorafenib, particularly on the per-protocol analysis.

Presenting the overall survival results, Germani said that there was no significant difference between the groups on the intention-to-treat analysis, at a stratified hazard ratio of 1.13 (P = .440), or on the per-protocol analysis, at a hazard ratio of 1.07 (P = .730).

“We then ran a subgroup analysis,” he continued, “and we found out that an anti-EGFR-free interval before liquid biopsy shorter than 6 months was associated with less benefit from a panitumumab [first] sequence, which is biologically sound.”

It was also observed that women did significantly better when having panitumumab first, whereas men did not, for which “we do not have a clear biological explanation,” Germani added.

Confining the analysis to so-called “hyperselected” patients, who not only were RAS and BRAF wild type but also had no pathogenic mutations associated with anti-EGFR resistance, did not reveal any significant overall survival differences between the treatment groups.

However, Ducreux took issue with the way in which hyperselection, which is turning up more and more regularly in trials, is defined, as the choice of which mutations to include varies widely. He suggested that a consensus group be assembled to resolve this issue.

Looking more broadly, the researchers were able to show that, in this updated analysis, anti-EGFR re-treatment was superior to regorafenib regardless of the treatment sequence in terms of PFS, at 4.2 months vs 2.4 months (P = .103) when given first in the trial, and 3.9 months vs 2.7 months (P = .019) when given second in the trial, as well as in terms of objective response and disease control rates.

 

Adverse Events

In terms of safety, the results showed that, as expected, acneiform rash, fatigue, and hypomagnesemia were the most common adverse events associated with panitumumb, while those with regorafenib were fatigue, hand-foot skin reactions, and hypertension.

There were no notable differences in the number of patients receiving a post-study treatment nor in the post-study therapeutic choices, between the study arms.

The study was sponsored by GONO Foundation and partially supported by Amgen and Bayer. Germani declared having relationships with MSD and Amgen. Ducreux declared having relationships with Amgen, Bayer, BeiGene, Incyte, Jazz, Merck KGaA, Merck Serono, Merck Sharp & Dohme, Pierre Fabre, Roche, Servier, Keocyt, AbbVie, Abcely, Arcus, Bayer, BMS, Boehringer, GlaxoSmithKline, Sanofi, Scandion, and Zymeworks.

A version of this article first appeared on Medscape.com.

BERLIN — Re-treatment with an antiepidermal growth factor receptor (EGFR) agent is effective in patients with chemorefractory metastatic colorectal cancer (mCRC) with RAS and BRAF wild-type tumors confirmed on circulating tumor DNA (ctDNA), although the sequencing of therapy does not seem to matter, suggest overall survival results from the crossover trial PARERE.

The findings nevertheless indicate that anti-EGFR rechallenge with panitumumab may prolong progression-free survival (PFS) over the multiple kinase inhibitor regorafenib. This suggests that “the most pragmatic choice” would be to give the anti-EGFR before regorafenib, said study presenter Marco Maria Germani, MD, Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy.

The caveat, however, is in patients who have an anti-EGFR interval since previously receiving the drugs of < 6 months. Those patients appeared to do better if they had regorafenib first and then anti-EGFR rechallenge.

Overall, Germani said that “since [trifluridine/tipiracil] plus bevacizumab is today the third-line standard of care” in this patient population, “anti-EGFR re-treatment might be considered after progression” on that combination.

Germani presented the research on October 18 at the European Society for Medical Oncology (ESMO) Annual Meeting 2025, which was simultaneously published in the Annals of Oncology.

Michel P. Ducreux, MD, PhD, head of the Digestive Cancer Committee at Gustave Roussy, Villejuif, France, and invited discussant for the results, said, despite the study being negative, it is “very important to continue to perform this kind of trial to evaluate the [ideal] sequence in the treatment of our patients.”

He continued that the secondary endpoints in the trial of PFS and objective response and disease control rates were “fairly in favor of the use of rechallenge before regorafenib, and in my opinion, this is really quite convincing.”

Ducreux, who was not involved in PARERE trail, also pointed to the sex difference seen in the study, which suggested that women responded much better to having anti-EGFR retreatment before regorafenib than did men.

Similar findings have been reported in a number of other trials, and previous work has suggested that there are sex differences in the pharmacokinetics of several anticancer drugs. However, while this is “very important,” he said that “we never consider it, because we are not able to really explain [it].”

Overall, he concluded that, on the basis of these results, he would agree with the notion that it is better to propose a rechallenge with anti-EGFR treatment as the fourth-line therapy in this patient population, before administering regorafenib.

Ducreux explained that, after a partial response, tumors acquire resistance to EGFR inhibitors through alterations and mutations that occur during treatment, via nongenetic mechanisms, and through treatment-induced selection for preexisting mutations.

Previous work has shown that mutations, such as in the RAS gene, are detectable early during EGFR inhibitor therapy, but that they then decay exponentially once the drugs are stopped, with the potential that tumors regain their sensitivity to them.

Germani said that this means that ctDNA-guided retreatment with anti-EGFR therapies is a “promising approach” in pretreated patients with RAS and BRAF wild-type mCRC, and that the sequencing of the drugs may be important. Indeed, the REVERCE trial showed that giving regorafenib followed by the anti-EGFR drug cetuzximab was associated with longer overall survival than the other way around in anti-EGFR medication-naive patients.

 

Methods and Results

For PARERE, the researchers enrolled patients aged at least 18 years with RAS and BRAF wild-type mCRC who were previously treated with a first-line anti-EGFR-containing regimen and had at least a partial response or stable disease for at least 6 months.

The patients were also required to have had at least one intervening anti-EGFR-free line of therapy, and to have previously received treatment with fluoropyrimidine, oxaliplatin, irinotecan, and anti-angiogenics. At least 4 months were required to have passed between the end of anti-EGFR administration and screening for the study.

In all, 428 patients were screened between December 2020 and December 2024, with 213 patients with RAS and BRAF wild-type mCRC, as detected on ctDNA, enrolled. They were randomized to panitumumab or regorafenib until first progression, followed by regorafenib, if they started on panitumumab, or panitumumab, if they started on regorafenib, until second progression.

The median age of the patients was 61 years among those who started on panitumumab and 64 years among those initially given regorafenib in the trial, and 63% and 57%, respectively, were male. The median number of prior lines of therapy was two in both groups, and 65% and 69%, respectively, had received pantitumumab as their first-line anti-EGFR.

Initial findings from the study presented at the 2025 ASCO Annual Meeting indicated that, after a median follow-up of 23.5 months, there was no significant difference in the median first PFS between the two treatment arms.

However, patients who started with panitumumab had a significant improvement in both the objective response and disease control rates (P < .001), as well as a signal for a potentially longer median second PFS, than those who started with regorafenib, particularly on the per-protocol analysis.

Presenting the overall survival results, Germani said that there was no significant difference between the groups on the intention-to-treat analysis, at a stratified hazard ratio of 1.13 (P = .440), or on the per-protocol analysis, at a hazard ratio of 1.07 (P = .730).

“We then ran a subgroup analysis,” he continued, “and we found out that an anti-EGFR-free interval before liquid biopsy shorter than 6 months was associated with less benefit from a panitumumab [first] sequence, which is biologically sound.”

It was also observed that women did significantly better when having panitumumab first, whereas men did not, for which “we do not have a clear biological explanation,” Germani added.

Confining the analysis to so-called “hyperselected” patients, who not only were RAS and BRAF wild type but also had no pathogenic mutations associated with anti-EGFR resistance, did not reveal any significant overall survival differences between the treatment groups.

However, Ducreux took issue with the way in which hyperselection, which is turning up more and more regularly in trials, is defined, as the choice of which mutations to include varies widely. He suggested that a consensus group be assembled to resolve this issue.

Looking more broadly, the researchers were able to show that, in this updated analysis, anti-EGFR re-treatment was superior to regorafenib regardless of the treatment sequence in terms of PFS, at 4.2 months vs 2.4 months (P = .103) when given first in the trial, and 3.9 months vs 2.7 months (P = .019) when given second in the trial, as well as in terms of objective response and disease control rates.

 

Adverse Events

In terms of safety, the results showed that, as expected, acneiform rash, fatigue, and hypomagnesemia were the most common adverse events associated with panitumumb, while those with regorafenib were fatigue, hand-foot skin reactions, and hypertension.

There were no notable differences in the number of patients receiving a post-study treatment nor in the post-study therapeutic choices, between the study arms.

The study was sponsored by GONO Foundation and partially supported by Amgen and Bayer. Germani declared having relationships with MSD and Amgen. Ducreux declared having relationships with Amgen, Bayer, BeiGene, Incyte, Jazz, Merck KGaA, Merck Serono, Merck Sharp & Dohme, Pierre Fabre, Roche, Servier, Keocyt, AbbVie, Abcely, Arcus, Bayer, BMS, Boehringer, GlaxoSmithKline, Sanofi, Scandion, and Zymeworks.

A version of this article first appeared on Medscape.com.

BERLIN — Re-treatment with an antiepidermal growth factor receptor (EGFR) agent is effective in patients with chemorefractory metastatic colorectal cancer (mCRC) with RAS and BRAF wild-type tumors confirmed on circulating tumor DNA (ctDNA), although the sequencing of therapy does not seem to matter, suggest overall survival results from the crossover trial PARERE.

The findings nevertheless indicate that anti-EGFR rechallenge with panitumumab may prolong progression-free survival (PFS) over the multiple kinase inhibitor regorafenib. This suggests that “the most pragmatic choice” would be to give the anti-EGFR before regorafenib, said study presenter Marco Maria Germani, MD, Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy.

The caveat, however, is in patients who have an anti-EGFR interval since previously receiving the drugs of < 6 months. Those patients appeared to do better if they had regorafenib first and then anti-EGFR rechallenge.

Overall, Germani said that “since [trifluridine/tipiracil] plus bevacizumab is today the third-line standard of care” in this patient population, “anti-EGFR re-treatment might be considered after progression” on that combination.

Germani presented the research on October 18 at the European Society for Medical Oncology (ESMO) Annual Meeting 2025, which was simultaneously published in the Annals of Oncology.

Michel P. Ducreux, MD, PhD, head of the Digestive Cancer Committee at Gustave Roussy, Villejuif, France, and invited discussant for the results, said, despite the study being negative, it is “very important to continue to perform this kind of trial to evaluate the [ideal] sequence in the treatment of our patients.”

He continued that the secondary endpoints in the trial of PFS and objective response and disease control rates were “fairly in favor of the use of rechallenge before regorafenib, and in my opinion, this is really quite convincing.”

Ducreux, who was not involved in PARERE trail, also pointed to the sex difference seen in the study, which suggested that women responded much better to having anti-EGFR retreatment before regorafenib than did men.

Similar findings have been reported in a number of other trials, and previous work has suggested that there are sex differences in the pharmacokinetics of several anticancer drugs. However, while this is “very important,” he said that “we never consider it, because we are not able to really explain [it].”

Overall, he concluded that, on the basis of these results, he would agree with the notion that it is better to propose a rechallenge with anti-EGFR treatment as the fourth-line therapy in this patient population, before administering regorafenib.

Ducreux explained that, after a partial response, tumors acquire resistance to EGFR inhibitors through alterations and mutations that occur during treatment, via nongenetic mechanisms, and through treatment-induced selection for preexisting mutations.

Previous work has shown that mutations, such as in the RAS gene, are detectable early during EGFR inhibitor therapy, but that they then decay exponentially once the drugs are stopped, with the potential that tumors regain their sensitivity to them.

Germani said that this means that ctDNA-guided retreatment with anti-EGFR therapies is a “promising approach” in pretreated patients with RAS and BRAF wild-type mCRC, and that the sequencing of the drugs may be important. Indeed, the REVERCE trial showed that giving regorafenib followed by the anti-EGFR drug cetuzximab was associated with longer overall survival than the other way around in anti-EGFR medication-naive patients.

 

Methods and Results

For PARERE, the researchers enrolled patients aged at least 18 years with RAS and BRAF wild-type mCRC who were previously treated with a first-line anti-EGFR-containing regimen and had at least a partial response or stable disease for at least 6 months.

The patients were also required to have had at least one intervening anti-EGFR-free line of therapy, and to have previously received treatment with fluoropyrimidine, oxaliplatin, irinotecan, and anti-angiogenics. At least 4 months were required to have passed between the end of anti-EGFR administration and screening for the study.

In all, 428 patients were screened between December 2020 and December 2024, with 213 patients with RAS and BRAF wild-type mCRC, as detected on ctDNA, enrolled. They were randomized to panitumumab or regorafenib until first progression, followed by regorafenib, if they started on panitumumab, or panitumumab, if they started on regorafenib, until second progression.

The median age of the patients was 61 years among those who started on panitumumab and 64 years among those initially given regorafenib in the trial, and 63% and 57%, respectively, were male. The median number of prior lines of therapy was two in both groups, and 65% and 69%, respectively, had received pantitumumab as their first-line anti-EGFR.

Initial findings from the study presented at the 2025 ASCO Annual Meeting indicated that, after a median follow-up of 23.5 months, there was no significant difference in the median first PFS between the two treatment arms.

However, patients who started with panitumumab had a significant improvement in both the objective response and disease control rates (P < .001), as well as a signal for a potentially longer median second PFS, than those who started with regorafenib, particularly on the per-protocol analysis.

Presenting the overall survival results, Germani said that there was no significant difference between the groups on the intention-to-treat analysis, at a stratified hazard ratio of 1.13 (P = .440), or on the per-protocol analysis, at a hazard ratio of 1.07 (P = .730).

“We then ran a subgroup analysis,” he continued, “and we found out that an anti-EGFR-free interval before liquid biopsy shorter than 6 months was associated with less benefit from a panitumumab [first] sequence, which is biologically sound.”

It was also observed that women did significantly better when having panitumumab first, whereas men did not, for which “we do not have a clear biological explanation,” Germani added.

Confining the analysis to so-called “hyperselected” patients, who not only were RAS and BRAF wild type but also had no pathogenic mutations associated with anti-EGFR resistance, did not reveal any significant overall survival differences between the treatment groups.

However, Ducreux took issue with the way in which hyperselection, which is turning up more and more regularly in trials, is defined, as the choice of which mutations to include varies widely. He suggested that a consensus group be assembled to resolve this issue.

Looking more broadly, the researchers were able to show that, in this updated analysis, anti-EGFR re-treatment was superior to regorafenib regardless of the treatment sequence in terms of PFS, at 4.2 months vs 2.4 months (P = .103) when given first in the trial, and 3.9 months vs 2.7 months (P = .019) when given second in the trial, as well as in terms of objective response and disease control rates.

 

Adverse Events

In terms of safety, the results showed that, as expected, acneiform rash, fatigue, and hypomagnesemia were the most common adverse events associated with panitumumb, while those with regorafenib were fatigue, hand-foot skin reactions, and hypertension.

There were no notable differences in the number of patients receiving a post-study treatment nor in the post-study therapeutic choices, between the study arms.

The study was sponsored by GONO Foundation and partially supported by Amgen and Bayer. Germani declared having relationships with MSD and Amgen. Ducreux declared having relationships with Amgen, Bayer, BeiGene, Incyte, Jazz, Merck KGaA, Merck Serono, Merck Sharp & Dohme, Pierre Fabre, Roche, Servier, Keocyt, AbbVie, Abcely, Arcus, Bayer, BMS, Boehringer, GlaxoSmithKline, Sanofi, Scandion, and Zymeworks.

A version of this article first appeared on Medscape.com.

In 2020, the US Multi-Society Task Force (USMSTF) on Colorectal Cancer (CRC) increased the recommended colon polyp surveillance interval for 1 to 2 subcentimeter tubular adenomas from 5 to 10 years to 7 to 10 years.¹ This change was prompted by emerging research indicating that rates of CRC and advanced neoplasia among patients with a history of only 1 to 2 subcentimeter tubular adenomas are lower than initially estimated.^2,3 This extension provides an opportunity to increase endoscopy capacity and improve access to colonoscopies by retroactively applying the 2020 guidelines to surveillance interval recommendations made before their introduction. For example, based on the updated guidelines, patients previously recommended to undergo colon polyp surveillance colonoscopy 5 years after an index colonoscopy could extend their surveillance interval by 2 to 5 years. Increasing endoscopic capacity could address the growing demand for colonoscopies from new screening guidelines that reduced the age of initial CRC screening from 50 years to 45 years and the backlog of procedures due to COVID-19 restrictions.⁴

As part of a project to increase endoscopic capacity at the US Department of Veterans Affairs (VA) Pittsburgh Healthcare System (VAPHS), this study assessed the potential impact of retroactively applying the 2020 USMSTF polyp surveillance guidelines on endoscopic capacity. These results may be informative for other VA and private-sector health care systems seeking to identify strategies to improve endoscopy capacity.

Methods

VAPHS is an integrated health care system in the Veterans Health Administration (VHA) serving 85,000 patients across 8 health care institutions in Pennsylvania, Ohio, and West Virginia. VAPHS manages colorectal screening recommendations for patients receiving medical care in the health care system regardless of whether their prior colonoscopy was performed at VAPHS or external facilities. The VA maintains a national CRC screening and surveillance electronic medical record reminder that prompts health care practitioners to order colon polyp surveillance based on interval recommendations from the index colonoscopy. This study reviewed all patients from the VAPHS panel with a reminder to undergo colonoscopy for screening for CRC or surveillance of colon polyps within 12 months from September 1, 2022.

Among patients with a reminder, 3 investigators reviewed index colonoscopy and pathology reports to identify CRC risk category, colonoscopy indication, procedural quality, and recommended repeat colonoscopy interval. Per the USMSTF guidelines, patients with incomplete colonoscopy or pathology records, high-risk indications (ie, personal history of inflammatory bowel disease, personal history of CRC, or family history of CRC), or inadequate bowel preparation (Boston Bowel Preparation Score < 6) were excluded. Additionally, patients who had CRC screening or surveillance discontinued due to age or comorbidities, had completed a subsequent follow-up colonoscopy, or were deceased at the time of review were excluded.

Retroactive Interval Reclassification

Among eligible patients, this study compared the repeat colonoscopy interval recommended by the prior endoscopist with those from the 2020 USMSTF guidelines. In cases where the interval was documented as a range of years, the lower end was considered the recommendation. Similarly, the lower end of the range from the 2020 USMSTF guidelines was used for the reclassified surveillance interval. Years extended per patient were quantified relative to September 1, 2023 (ie, 1 year after the review date). For example, if the index colonoscopy was completed on September 1, 2016, the initial surveillance recommendation was 5 years, and the reclassified recommendation was 7 years, the interval extension beyond September 1, 2023, was 0 years.

Furthermore, because index surveillance recommendations are not always guideline concordant, the years extended per patient were calculated by harmonizing the index endoscopist’s recommendations with the guidelines at the time of the index colonoscopy.⁵ For example, if the index colonoscopy was completed on September 1, 2018, and the endoscopist recommended a 5-year follow-up for a patient with average risk for CRC, adequate bowel preparation, and no colorectal polyps, that patient is eligible to extend their colonoscopy to September 1, 2028, based on guideline recommendations at the time of index endoscopy recommending that the next colonoscopy occur in 10 years. In this analysis the 2012 USMSTF guidelines were applied to all index colonoscopies completed in 2021 or earlier to allow time for adoption of the 2020 guidelines. 

This project fulfilled a facility mandate to increase capacity to conduct endoscopic procedures. Institutional review board approval was not required by VAPHS policy relating to clinical operations projects. Approval for publication of clinical operations activity was obtained from the VAPHS facility director.

Results

Within 1 year of the September 1, 2022, review date, 637 patients receiving care at VAPHS had clinical reminders for an upcoming colonoscopy. Of these, 54 (8.4%) were already up to date or were deceased at the time of review. Of the 583 eligible patients, 96% were male, the median age was 74 years, the median index colonoscopy year was 2016, and 178 (30.5%) had an average-risk CRC screening indication at the index colonoscopy (Table).

Of the 583 patients due for colonoscopy, 331 (56.7%) had both colonoscopy and pathology reports available. The majority of those with incomplete records had the index colonoscopy completed outside VAPHS. Among these patients, 222 (67.0%) had adequate bowel preparation. Of those with adequate bowel preparation, 43 were not eligible for interval extension because of high-risk conditions and 13 were not eligible because there was no index surveillance interval recommendation from the index endoscopist. Of the patients due for colonoscopy, 166 (28.4%) were potentially eligible for surveillance interval extension (Figure).  

Sixty-five (39.2%) of the 166 patients had 1 to 2 subcentimeter tubular adenomas on their index colonoscopy. Sixty-two patients were eligible for interval extension to 7 years, but this only resulted in ≥ 1 year of extension beyond the review date for 36 (6% of all 583 patients due for colonoscopy). The 36 patients were extended 63 years. By harmonizing the index endoscopists’ surveillance interval recommendation with the guideline at the time of the index colonoscopy, 29 additional patients could have their colonoscopy extended by ≥ 1 year. Harmonization extended colonoscopy intervals by 93 years. Retroactively applying the 2020 USMSTF polyp surveillance guidelines and harmonizing recommendations to guidelines extended the time of index colonoscopy by 153 years.

Discussion

With retroactive application of the 2020 USMSTF polyp surveillance guidelines, 6% of patients due for an upcoming colonoscopy could extend their follow-up by ≥ 1 year by extending the surveillance interval for 1 to 2 subcentimeter tubular adenomas to 7 years. An additional 5% of patients could extend their interval by harmonizing the index endoscopist’s interval recommendation with polyp surveillance guidelines at the time of the index colonoscopy. These findings are consistent with the results of 2 studies that demonstrated that about 14% of patients due for colonoscopy could have their interval extended.^6,7 The current study enhances those insights by separating the contribution of 2020 USMSTF polyp surveillance guidelines from the contribution of harmonizing surveillance intervals with guidelines for other polyp histologies. This study found that there is an opportunity to improve endoscopic capacity by harmonizing recommendations with guidelines. This complements a 2023 study showing that even when knowledgeable about guidelines, clinicians do not necessarily follow recommendations.⁸ While this and previous research have identified that 11% to 14% of patients are eligible for extension, these individuals would also have to be willing to have their polyp surveillance intervals extended for there to be a real-world impact on endoscopic capacity. A 2024 study found that only 19% to 37% of patients with 1 to 2 small tubular adenomas were willing to have polyps surveillance interval extension.⁹ This suggests the actual effect on capacity may be even lower than reported.

Limitations

The overall impact of the 2020 USMSTF polyp surveillance guidelines on endoscopic capacity was blunted by the high prevalence of incomplete index colonoscopy records among the study population. Without data on bowel preparation quality or procedure indications, this study could not assess whether 43% of patients were eligible for surveillance interval extension. Most index colonoscopies with incomplete documentation were completed at community-care gastroenterology facilities. This high rate of incomplete documentation is likely generalizable to other VA health care systems—especially in the era of the Veterans Access, Choice, and Accountability Act of 2014, which increased veteran access to non-VA community care.¹⁰ Veterans due for colon polyp surveillance colonoscopies are more likely to have had their prior colonoscopy in community care compared with prior eras.¹¹ Furthermore, because the VHA is among the most established integrated health care systems offering primary and subspecialty care in the US, private sector health care systems may have even greater rates of care fragmentation for longitudinal CRC screening and colon polyp surveillance, as these systems have only begun to regionally integrate recently.^12,13

Another limitation is that nearly one-third of the individuals with documentation had inadequate bowel preparation for surveillance recommendations. This results in shorter surveillance follow-up colonoscopies and increases downstream demand for future colonoscopies. The low yield of extending colon polyp surveillance interval in this study emphasizes that improved efforts to obtain colonoscopy and pathology reports from community care, right-sizing the colon polyp surveillance intervals recommended by endoscopists, and improving quality of bowel preparation could have downstream health care system benefits in the future. These efforts could increase colonoscopy capacity at VA health care systems, thereby shortening colonoscopy wait times, decreasing fragmentation of care, and increasing the number of veterans who receive high-quality colonoscopies at VA health care systems.¹⁴

Conclusions

Eleven percent of patients in this study due for a colonoscopy could extend their follow-up by ≥ 1 year. About half of these extensions were directly due to the 2020 USMSTF polyp surveillance interval extension for 1 to 2 subcentimeter tubular adenomas. The rest resulted from harmonizing recommendations with guidelines at the time of the procedure. To determine whether retroactively applying polyp surveillance guidelines to follow-up interval recommendations will result in improved endoscopic capacity, health care system administrators should consider the degree of CRC screening care fragmentation in their patient population. Greater long-term gains in endoscopic capacity may be achieved by proactively supporting endoscopists in making guideline-concordant screening recommendations at the time of colonoscopy.

In 2020, the US Multi-Society Task Force (USMSTF) on Colorectal Cancer (CRC) increased the recommended colon polyp surveillance interval for 1 to 2 subcentimeter tubular adenomas from 5 to 10 years to 7 to 10 years.¹ This change was prompted by emerging research indicating that rates of CRC and advanced neoplasia among patients with a history of only 1 to 2 subcentimeter tubular adenomas are lower than initially estimated.^2,3 This extension provides an opportunity to increase endoscopy capacity and improve access to colonoscopies by retroactively applying the 2020 guidelines to surveillance interval recommendations made before their introduction. For example, based on the updated guidelines, patients previously recommended to undergo colon polyp surveillance colonoscopy 5 years after an index colonoscopy could extend their surveillance interval by 2 to 5 years. Increasing endoscopic capacity could address the growing demand for colonoscopies from new screening guidelines that reduced the age of initial CRC screening from 50 years to 45 years and the backlog of procedures due to COVID-19 restrictions.⁴

As part of a project to increase endoscopic capacity at the US Department of Veterans Affairs (VA) Pittsburgh Healthcare System (VAPHS), this study assessed the potential impact of retroactively applying the 2020 USMSTF polyp surveillance guidelines on endoscopic capacity. These results may be informative for other VA and private-sector health care systems seeking to identify strategies to improve endoscopy capacity.

Methods

VAPHS is an integrated health care system in the Veterans Health Administration (VHA) serving 85,000 patients across 8 health care institutions in Pennsylvania, Ohio, and West Virginia. VAPHS manages colorectal screening recommendations for patients receiving medical care in the health care system regardless of whether their prior colonoscopy was performed at VAPHS or external facilities. The VA maintains a national CRC screening and surveillance electronic medical record reminder that prompts health care practitioners to order colon polyp surveillance based on interval recommendations from the index colonoscopy. This study reviewed all patients from the VAPHS panel with a reminder to undergo colonoscopy for screening for CRC or surveillance of colon polyps within 12 months from September 1, 2022.

Among patients with a reminder, 3 investigators reviewed index colonoscopy and pathology reports to identify CRC risk category, colonoscopy indication, procedural quality, and recommended repeat colonoscopy interval. Per the USMSTF guidelines, patients with incomplete colonoscopy or pathology records, high-risk indications (ie, personal history of inflammatory bowel disease, personal history of CRC, or family history of CRC), or inadequate bowel preparation (Boston Bowel Preparation Score < 6) were excluded. Additionally, patients who had CRC screening or surveillance discontinued due to age or comorbidities, had completed a subsequent follow-up colonoscopy, or were deceased at the time of review were excluded.

Retroactive Interval Reclassification

Among eligible patients, this study compared the repeat colonoscopy interval recommended by the prior endoscopist with those from the 2020 USMSTF guidelines. In cases where the interval was documented as a range of years, the lower end was considered the recommendation. Similarly, the lower end of the range from the 2020 USMSTF guidelines was used for the reclassified surveillance interval. Years extended per patient were quantified relative to September 1, 2023 (ie, 1 year after the review date). For example, if the index colonoscopy was completed on September 1, 2016, the initial surveillance recommendation was 5 years, and the reclassified recommendation was 7 years, the interval extension beyond September 1, 2023, was 0 years.

Furthermore, because index surveillance recommendations are not always guideline concordant, the years extended per patient were calculated by harmonizing the index endoscopist’s recommendations with the guidelines at the time of the index colonoscopy.⁵ For example, if the index colonoscopy was completed on September 1, 2018, and the endoscopist recommended a 5-year follow-up for a patient with average risk for CRC, adequate bowel preparation, and no colorectal polyps, that patient is eligible to extend their colonoscopy to September 1, 2028, based on guideline recommendations at the time of index endoscopy recommending that the next colonoscopy occur in 10 years. In this analysis the 2012 USMSTF guidelines were applied to all index colonoscopies completed in 2021 or earlier to allow time for adoption of the 2020 guidelines. 

This project fulfilled a facility mandate to increase capacity to conduct endoscopic procedures. Institutional review board approval was not required by VAPHS policy relating to clinical operations projects. Approval for publication of clinical operations activity was obtained from the VAPHS facility director.

Results

Within 1 year of the September 1, 2022, review date, 637 patients receiving care at VAPHS had clinical reminders for an upcoming colonoscopy. Of these, 54 (8.4%) were already up to date or were deceased at the time of review. Of the 583 eligible patients, 96% were male, the median age was 74 years, the median index colonoscopy year was 2016, and 178 (30.5%) had an average-risk CRC screening indication at the index colonoscopy (Table).

Of the 583 patients due for colonoscopy, 331 (56.7%) had both colonoscopy and pathology reports available. The majority of those with incomplete records had the index colonoscopy completed outside VAPHS. Among these patients, 222 (67.0%) had adequate bowel preparation. Of those with adequate bowel preparation, 43 were not eligible for interval extension because of high-risk conditions and 13 were not eligible because there was no index surveillance interval recommendation from the index endoscopist. Of the patients due for colonoscopy, 166 (28.4%) were potentially eligible for surveillance interval extension (Figure).  

Sixty-five (39.2%) of the 166 patients had 1 to 2 subcentimeter tubular adenomas on their index colonoscopy. Sixty-two patients were eligible for interval extension to 7 years, but this only resulted in ≥ 1 year of extension beyond the review date for 36 (6% of all 583 patients due for colonoscopy). The 36 patients were extended 63 years. By harmonizing the index endoscopists’ surveillance interval recommendation with the guideline at the time of the index colonoscopy, 29 additional patients could have their colonoscopy extended by ≥ 1 year. Harmonization extended colonoscopy intervals by 93 years. Retroactively applying the 2020 USMSTF polyp surveillance guidelines and harmonizing recommendations to guidelines extended the time of index colonoscopy by 153 years.

Discussion

With retroactive application of the 2020 USMSTF polyp surveillance guidelines, 6% of patients due for an upcoming colonoscopy could extend their follow-up by ≥ 1 year by extending the surveillance interval for 1 to 2 subcentimeter tubular adenomas to 7 years. An additional 5% of patients could extend their interval by harmonizing the index endoscopist’s interval recommendation with polyp surveillance guidelines at the time of the index colonoscopy. These findings are consistent with the results of 2 studies that demonstrated that about 14% of patients due for colonoscopy could have their interval extended.^6,7 The current study enhances those insights by separating the contribution of 2020 USMSTF polyp surveillance guidelines from the contribution of harmonizing surveillance intervals with guidelines for other polyp histologies. This study found that there is an opportunity to improve endoscopic capacity by harmonizing recommendations with guidelines. This complements a 2023 study showing that even when knowledgeable about guidelines, clinicians do not necessarily follow recommendations.⁸ While this and previous research have identified that 11% to 14% of patients are eligible for extension, these individuals would also have to be willing to have their polyp surveillance intervals extended for there to be a real-world impact on endoscopic capacity. A 2024 study found that only 19% to 37% of patients with 1 to 2 small tubular adenomas were willing to have polyps surveillance interval extension.⁹ This suggests the actual effect on capacity may be even lower than reported.

Limitations

The overall impact of the 2020 USMSTF polyp surveillance guidelines on endoscopic capacity was blunted by the high prevalence of incomplete index colonoscopy records among the study population. Without data on bowel preparation quality or procedure indications, this study could not assess whether 43% of patients were eligible for surveillance interval extension. Most index colonoscopies with incomplete documentation were completed at community-care gastroenterology facilities. This high rate of incomplete documentation is likely generalizable to other VA health care systems—especially in the era of the Veterans Access, Choice, and Accountability Act of 2014, which increased veteran access to non-VA community care.¹⁰ Veterans due for colon polyp surveillance colonoscopies are more likely to have had their prior colonoscopy in community care compared with prior eras.¹¹ Furthermore, because the VHA is among the most established integrated health care systems offering primary and subspecialty care in the US, private sector health care systems may have even greater rates of care fragmentation for longitudinal CRC screening and colon polyp surveillance, as these systems have only begun to regionally integrate recently.^12,13

Another limitation is that nearly one-third of the individuals with documentation had inadequate bowel preparation for surveillance recommendations. This results in shorter surveillance follow-up colonoscopies and increases downstream demand for future colonoscopies. The low yield of extending colon polyp surveillance interval in this study emphasizes that improved efforts to obtain colonoscopy and pathology reports from community care, right-sizing the colon polyp surveillance intervals recommended by endoscopists, and improving quality of bowel preparation could have downstream health care system benefits in the future. These efforts could increase colonoscopy capacity at VA health care systems, thereby shortening colonoscopy wait times, decreasing fragmentation of care, and increasing the number of veterans who receive high-quality colonoscopies at VA health care systems.¹⁴

Conclusions

Eleven percent of patients in this study due for a colonoscopy could extend their follow-up by ≥ 1 year. About half of these extensions were directly due to the 2020 USMSTF polyp surveillance interval extension for 1 to 2 subcentimeter tubular adenomas. The rest resulted from harmonizing recommendations with guidelines at the time of the procedure. To determine whether retroactively applying polyp surveillance guidelines to follow-up interval recommendations will result in improved endoscopic capacity, health care system administrators should consider the degree of CRC screening care fragmentation in their patient population. Greater long-term gains in endoscopic capacity may be achieved by proactively supporting endoscopists in making guideline-concordant screening recommendations at the time of colonoscopy.

In 2020, the US Multi-Society Task Force (USMSTF) on Colorectal Cancer (CRC) increased the recommended colon polyp surveillance interval for 1 to 2 subcentimeter tubular adenomas from 5 to 10 years to 7 to 10 years.¹ This change was prompted by emerging research indicating that rates of CRC and advanced neoplasia among patients with a history of only 1 to 2 subcentimeter tubular adenomas are lower than initially estimated.^2,3 This extension provides an opportunity to increase endoscopy capacity and improve access to colonoscopies by retroactively applying the 2020 guidelines to surveillance interval recommendations made before their introduction. For example, based on the updated guidelines, patients previously recommended to undergo colon polyp surveillance colonoscopy 5 years after an index colonoscopy could extend their surveillance interval by 2 to 5 years. Increasing endoscopic capacity could address the growing demand for colonoscopies from new screening guidelines that reduced the age of initial CRC screening from 50 years to 45 years and the backlog of procedures due to COVID-19 restrictions.⁴

As part of a project to increase endoscopic capacity at the US Department of Veterans Affairs (VA) Pittsburgh Healthcare System (VAPHS), this study assessed the potential impact of retroactively applying the 2020 USMSTF polyp surveillance guidelines on endoscopic capacity. These results may be informative for other VA and private-sector health care systems seeking to identify strategies to improve endoscopy capacity.

Methods

VAPHS is an integrated health care system in the Veterans Health Administration (VHA) serving 85,000 patients across 8 health care institutions in Pennsylvania, Ohio, and West Virginia. VAPHS manages colorectal screening recommendations for patients receiving medical care in the health care system regardless of whether their prior colonoscopy was performed at VAPHS or external facilities. The VA maintains a national CRC screening and surveillance electronic medical record reminder that prompts health care practitioners to order colon polyp surveillance based on interval recommendations from the index colonoscopy. This study reviewed all patients from the VAPHS panel with a reminder to undergo colonoscopy for screening for CRC or surveillance of colon polyps within 12 months from September 1, 2022.

Among patients with a reminder, 3 investigators reviewed index colonoscopy and pathology reports to identify CRC risk category, colonoscopy indication, procedural quality, and recommended repeat colonoscopy interval. Per the USMSTF guidelines, patients with incomplete colonoscopy or pathology records, high-risk indications (ie, personal history of inflammatory bowel disease, personal history of CRC, or family history of CRC), or inadequate bowel preparation (Boston Bowel Preparation Score < 6) were excluded. Additionally, patients who had CRC screening or surveillance discontinued due to age or comorbidities, had completed a subsequent follow-up colonoscopy, or were deceased at the time of review were excluded.

Retroactive Interval Reclassification

Among eligible patients, this study compared the repeat colonoscopy interval recommended by the prior endoscopist with those from the 2020 USMSTF guidelines. In cases where the interval was documented as a range of years, the lower end was considered the recommendation. Similarly, the lower end of the range from the 2020 USMSTF guidelines was used for the reclassified surveillance interval. Years extended per patient were quantified relative to September 1, 2023 (ie, 1 year after the review date). For example, if the index colonoscopy was completed on September 1, 2016, the initial surveillance recommendation was 5 years, and the reclassified recommendation was 7 years, the interval extension beyond September 1, 2023, was 0 years.

Furthermore, because index surveillance recommendations are not always guideline concordant, the years extended per patient were calculated by harmonizing the index endoscopist’s recommendations with the guidelines at the time of the index colonoscopy.⁵ For example, if the index colonoscopy was completed on September 1, 2018, and the endoscopist recommended a 5-year follow-up for a patient with average risk for CRC, adequate bowel preparation, and no colorectal polyps, that patient is eligible to extend their colonoscopy to September 1, 2028, based on guideline recommendations at the time of index endoscopy recommending that the next colonoscopy occur in 10 years. In this analysis the 2012 USMSTF guidelines were applied to all index colonoscopies completed in 2021 or earlier to allow time for adoption of the 2020 guidelines. 

This project fulfilled a facility mandate to increase capacity to conduct endoscopic procedures. Institutional review board approval was not required by VAPHS policy relating to clinical operations projects. Approval for publication of clinical operations activity was obtained from the VAPHS facility director.

Results

Within 1 year of the September 1, 2022, review date, 637 patients receiving care at VAPHS had clinical reminders for an upcoming colonoscopy. Of these, 54 (8.4%) were already up to date or were deceased at the time of review. Of the 583 eligible patients, 96% were male, the median age was 74 years, the median index colonoscopy year was 2016, and 178 (30.5%) had an average-risk CRC screening indication at the index colonoscopy (Table).

Of the 583 patients due for colonoscopy, 331 (56.7%) had both colonoscopy and pathology reports available. The majority of those with incomplete records had the index colonoscopy completed outside VAPHS. Among these patients, 222 (67.0%) had adequate bowel preparation. Of those with adequate bowel preparation, 43 were not eligible for interval extension because of high-risk conditions and 13 were not eligible because there was no index surveillance interval recommendation from the index endoscopist. Of the patients due for colonoscopy, 166 (28.4%) were potentially eligible for surveillance interval extension (Figure).  

Sixty-five (39.2%) of the 166 patients had 1 to 2 subcentimeter tubular adenomas on their index colonoscopy. Sixty-two patients were eligible for interval extension to 7 years, but this only resulted in ≥ 1 year of extension beyond the review date for 36 (6% of all 583 patients due for colonoscopy). The 36 patients were extended 63 years. By harmonizing the index endoscopists’ surveillance interval recommendation with the guideline at the time of the index colonoscopy, 29 additional patients could have their colonoscopy extended by ≥ 1 year. Harmonization extended colonoscopy intervals by 93 years. Retroactively applying the 2020 USMSTF polyp surveillance guidelines and harmonizing recommendations to guidelines extended the time of index colonoscopy by 153 years.

Discussion

With retroactive application of the 2020 USMSTF polyp surveillance guidelines, 6% of patients due for an upcoming colonoscopy could extend their follow-up by ≥ 1 year by extending the surveillance interval for 1 to 2 subcentimeter tubular adenomas to 7 years. An additional 5% of patients could extend their interval by harmonizing the index endoscopist’s interval recommendation with polyp surveillance guidelines at the time of the index colonoscopy. These findings are consistent with the results of 2 studies that demonstrated that about 14% of patients due for colonoscopy could have their interval extended.^6,7 The current study enhances those insights by separating the contribution of 2020 USMSTF polyp surveillance guidelines from the contribution of harmonizing surveillance intervals with guidelines for other polyp histologies. This study found that there is an opportunity to improve endoscopic capacity by harmonizing recommendations with guidelines. This complements a 2023 study showing that even when knowledgeable about guidelines, clinicians do not necessarily follow recommendations.⁸ While this and previous research have identified that 11% to 14% of patients are eligible for extension, these individuals would also have to be willing to have their polyp surveillance intervals extended for there to be a real-world impact on endoscopic capacity. A 2024 study found that only 19% to 37% of patients with 1 to 2 small tubular adenomas were willing to have polyps surveillance interval extension.⁹ This suggests the actual effect on capacity may be even lower than reported.

Limitations

The overall impact of the 2020 USMSTF polyp surveillance guidelines on endoscopic capacity was blunted by the high prevalence of incomplete index colonoscopy records among the study population. Without data on bowel preparation quality or procedure indications, this study could not assess whether 43% of patients were eligible for surveillance interval extension. Most index colonoscopies with incomplete documentation were completed at community-care gastroenterology facilities. This high rate of incomplete documentation is likely generalizable to other VA health care systems—especially in the era of the Veterans Access, Choice, and Accountability Act of 2014, which increased veteran access to non-VA community care.¹⁰ Veterans due for colon polyp surveillance colonoscopies are more likely to have had their prior colonoscopy in community care compared with prior eras.¹¹ Furthermore, because the VHA is among the most established integrated health care systems offering primary and subspecialty care in the US, private sector health care systems may have even greater rates of care fragmentation for longitudinal CRC screening and colon polyp surveillance, as these systems have only begun to regionally integrate recently.^12,13

Another limitation is that nearly one-third of the individuals with documentation had inadequate bowel preparation for surveillance recommendations. This results in shorter surveillance follow-up colonoscopies and increases downstream demand for future colonoscopies. The low yield of extending colon polyp surveillance interval in this study emphasizes that improved efforts to obtain colonoscopy and pathology reports from community care, right-sizing the colon polyp surveillance intervals recommended by endoscopists, and improving quality of bowel preparation could have downstream health care system benefits in the future. These efforts could increase colonoscopy capacity at VA health care systems, thereby shortening colonoscopy wait times, decreasing fragmentation of care, and increasing the number of veterans who receive high-quality colonoscopies at VA health care systems.¹⁴

Conclusions

Eleven percent of patients in this study due for a colonoscopy could extend their follow-up by ≥ 1 year. About half of these extensions were directly due to the 2020 USMSTF polyp surveillance interval extension for 1 to 2 subcentimeter tubular adenomas. The rest resulted from harmonizing recommendations with guidelines at the time of the procedure. To determine whether retroactively applying polyp surveillance guidelines to follow-up interval recommendations will result in improved endoscopic capacity, health care system administrators should consider the degree of CRC screening care fragmentation in their patient population. Greater long-term gains in endoscopic capacity may be achieved by proactively supporting endoscopists in making guideline-concordant screening recommendations at the time of colonoscopy.