The old rule-of-thumb did not work because “you once had a polyp, therefore see you in the endoscopy suite forever” is not a medical plan - it is a subscription service with worse snacks.
A new Gastroenterology digest by Sunil Samnani and Nauzer Forbes looks at a very practical question: after age 75, how much does a past adenoma really change someone’s future risk of colorectal cancer? The piece discusses a large 2026 JAMA study of older adults in the Veterans Affairs system, and the answer is both reassuring and slightly awkward for the medical autopilot button.
Yes, people with prior adenomas had a higher risk than people without them. But the absolute numbers were small. At 10 years, colorectal cancer occurred in 1.1% of those with a prior adenoma versus 0.7% without one. Death from colorectal cancer was 0.5% versus 0.4%. Meanwhile, death from causes other than colorectal cancer was in the neighborhood of 47% to 48% over 10 years Gupta et al., 2026.
That is the dinner table moment where everyone pauses over the salad.
The Polyp Was Real, But So Is the Rest of the Person
An adenoma is a benign glandular growth, often found as a colorectal polyp. Some adenomas can become cancer over time, which is why colonoscopy has long been the bouncer at the door, checking IDs and removing suspicious characters before they start trouble.
But cancer prevention in older adults is not just about whether a polyp once existed. It is about time, frailty, competing health risks, procedure burden, sedation risk, bowel prep misery, and whether the likely benefit arrives soon enough to matter. Bowel prep, let us be honest, already feels like a tiny home plumbing emergency with medical branding.
The JAMA study followed 91,952 veterans who had a colonoscopy before age 75. About 28% had an adenoma. The researchers then asked what happened after age 75: colorectal cancer, colorectal cancer death, death from other causes, and how frailty changed the picture.
Frailty mattered a lot. Among people with prior adenomas, colorectal cancer risk stayed low across frailty groups, while non-colorectal-cancer death ranged from 34.2% in nonfrail people to 82.0% in severely frail people at 10 years. In other words, the colon was not always the main plotline. Sometimes it was a subplot with excellent lighting.
Why This Is Not “Cancel All Colonoscopies”
This study does not say colonoscopy is useless. Colonoscopy can prevent colorectal cancer by finding and removing precancerous lesions. Screening has helped drive major declines in colorectal cancer incidence and mortality among older adults, and guidelines still support screening many average-risk adults through age 75, with individualized decisions from 76 to 85.
The point is more refined: surveillance after prior adenoma may not deserve automatic priority in every adult over 75.
That distinction matters because older adults are often managing a full medical group chat: heart disease, diabetes, kidney problems, mobility issues, medications, falls, cognition, independence. A surveillance colonoscopy may be worthwhile for a healthy 76-year-old with a prior advanced adenoma and a long life expectancy. It may be much less compelling for an 84-year-old with severe frailty, especially if the expected benefit is tiny and delayed.
A 2024 JAMA Network Open study made a similar point from another angle. Among 9,740 surveillance colonoscopies in adults aged 70 to 85 with prior adenomas, colorectal cancer was found in just 0.3% of procedures, although advanced adenomas were more common Lee et al., 2024. Translation: doctors found potential future trouble more often than current cancer, but whether removing that future trouble helps a specific older person depends on that person’s health horizon.
The Better Question
The old question was: “Did you ever have an adenoma?”
The better question is: “Will another colonoscopy meaningfully help you now?”
That is a much more human question. It lets clinicians consider prior polyp type, overall health, life expectancy, patient preferences, and alternatives like fecal immunochemical testing, which researchers are actively studying as a possible lower-burden surveillance strategy in older adults.
There is also a quiet health-system angle here. Colonoscopy capacity is finite. If some low-benefit surveillance can be safely de-escalated, those slots can go to people with symptoms, positive stool tests, high-risk histories, or no prior screening. Medicine loves a scarce resource almost as much as it loves an acronym, but this is one place where triage could actually make care kinder.
The Takeaway
This research nudges us away from reflex medicine and toward tailored medicine. Prior adenomas still matter. Colorectal cancer still matters. But after 75, the body becomes less like a single-problem worksheet and more like a dinner party seating chart: relationships, timing, and context change everything.
The most useful outcome of this study may be permission to have a better conversation. Not “Are we doing the colonoscopy because the calendar says so?” but “Given your health, your risks, and what you want, is this test still earning its place?”
That is not giving up on prevention. That is prevention growing up, putting on a nicer jacket, and reading the room.
References
-
Samnani S, Forbes N. Risk of Colorectal Cancer following Colonoscopy in Older Persons. Gastroenterology. Published online May 26, 2026. https://doi.org/10.1053/j.gastro.2026.05.011
-
Gupta S, Liu L, Demb J, et al. Colorectal Cancer and Mortality Risk Among Older Adults With vs Without Adenoma on Prior Colonoscopy. JAMA. 2026;335:1499-1506. https://doi.org/10.1001/jama.2026.3414
-
Lee JK, Roy A, Jensen CD, et al. Surveillance Colonoscopy Findings in Older Adults With a History of Colorectal Adenomas. JAMA Network Open. 2024;7(4):e244611. https://doi.org/10.1001/jamanetworkopen.2024.4611
-
Lin JS, Perdue LA, Henrikson NB, Bean SI, Blasi PR. Screening for Colorectal Cancer: Updated Evidence Report and Systematic Review for the US Preventive Services Task Force. JAMA. 2021;325(19):1978-1998. https://doi.org/10.1001/jama.2021.4417
Disclaimer: The image accompanying this article is for illustrative purposes only and does not depict actual experimental results, data, or biological mechanisms.