# Stool DNA screening's ten-year follow-up gap > A large retrospective programme found strong colonoscopy yields after positive multi-target stool DNA tests, but many people did not complete the next step on time or repeat a negative test as scheduled. _Source: The American Journal of Gastroenterology retrospective multi-site screening cohort, verified against PubMed PMID 42690929 and Telegram post 1486 · 2026-09-15 · 6 min read · Verified against primary sources_ Canonical: https://iyu.app/e/mt-sdna-ten-year-screening-follow-up ## The 60-second version A decade of real-world data found strong lesion detection after positive multi-target stool DNA tests, but large gaps in timely colonoscopy and repeat screening. **Key points** - The retrospective cohort included 148,624 tests from 110,410 people, with a 13.6% positivity rate. - Among positive tests, 65.1% led to colonoscopy within 12 months; advanced adenoma was reported in 30.7% and adenocarcinoma in 1.3% of follow-up colonoscopies. - Only 35.3% of people with a negative test repeated stool DNA screening within three years. - The study measured one multi-site programme and did not prove that the test reduces mortality or that delay caused later findings. **Verdict.** The weak point was not only test accuracy but follow-through: positive results need timely diagnostic colonoscopy, and negative results still need scheduled rescreening. ## Full explainer > **⚑ Caveat:** The paper is a retrospective analysis of one multi-site health system. Its results describe screening performance and follow-up in that programme; they do not prove that stool DNA testing reduces mortality or that the same numbers apply everywhere. ### The finding — The test worked best when the pathway continued Multi-target stool DNA testing is designed to find signals associated with colorectal cancer and precancerous lesions without an initial procedure. The study followed the programme's results for a decade, but its central lesson is about what happens after the result arrives: screening has value only when the next step is completed. - **148,624** — tests analysed - **13.6%** — positive tests - **65.1%** — positive tests followed by colonoscopy within 12 months ### After a positive result — Colonoscopy found important lesions The cohort included 19,506 positive tests. Among these, 65.1% were followed by colonoscopy within 12 months; the median wait was 82 days. In the resulting colonoscopies, advanced adenomas were diagnosed in 30.7% and adenocarcinoma in 1.3%. Those are findings among people who proceeded to colonoscopy, not a guarantee about any individual result. - **Measure:** What the study reported - **Advanced adenoma after a positive test:** 30.7% of follow-up colonoscopies - **Adenocarcinoma after a positive test:** 1.3% of follow-up colonoscopies - **Repeat testing after a negative test:** 35.3% completed another stool DNA test within 3 years ### The missing link — A negative result still has a timetable Only 35.3% of people with an initial negative result had another stool DNA test within three years. Among the smaller group who underwent colonoscopy within three years of a negative test, 45.2% had an adenoma or serrated lesion, 9.3% had an advanced adenoma, and 0.5% had colon cancer. Because this was a selected subgroup, these numbers cannot be treated as the test's population-wide false-negative rate. > **⚑ Caveat:** Do not turn these programme statistics into a personal diagnosis. A positive stool DNA result generally needs the follow-up recommended by a clinician; a negative result does not mean screening is finished. The appropriate interval depends on the test, age, risk, symptoms, and local guidance. ### How to read it — This is a care-cascade study, not a survival trial The researchers used retrospective records from September 2014 to July 2025 in a multi-site health system. A validated large-language-model pipeline extracted colonoscopy, pathology, and quality endpoints from free-text reports. The analysis found that adenoma detection after positive tests exceeded 50% and that waits longer than six months were associated with more advanced adenoma, with a trend P value of 0.001. Association is not proof that delay caused the finding, and the programme may differ from other health systems. > A screening test is not a single event. It is a chain: test, result, follow-up, and the next scheduled screen. ### The practical takeaway — Make the handoff impossible to miss The authors point to system-level tracking and reminders as the next opportunity. For readers, the useful question is not whether one test is good or bad in isolation, but whether a positive result has a documented follow-up plan and whether a negative result has a date for the next screen. That is how a convenient test can become a complete screening pathway. ## Primary sources - [Telegram source post 1486](https://t.me/CNSmydream/1486) - [Original paper DOI](https://doi.org/10.14309/ajg.0000000000004196) - [PubMed record PMID 42690929](https://pubmed.ncbi.nlm.nih.gov/42690929/) - [NCBI PubMed abstract endpoint](https://eutils.ncbi.nlm.nih.gov/entrez/eutils/efetch.fcgi?db=pubmed&id=42690929&retmode=xml) --- _Published by iyu (https://iyu.app) — the day's AI news, checked against primary sources and rewritten in plain language. Free to quote with attribution and a link to the canonical URL._