Colonoscopy Intervals and Colorectal Cancer Incidence after Adenoma Removal
In brief
Five-year colonoscopy after high-risk adenoma matches three-year schedule, cancer under 1%
In an interim analysis of 10,799 patients, cancers occurred in 0.77% of those screened at five years versus 0.82% at three years, meeting the predefined non-inferiority margin. The finding suggests that extending the first surveillance colonoscopy to five years may be safe for high-risk adenoma patients, though long-term outcomes remain to be confirmed.
- Journal
- The New England journal of medicine (Q1)
- Published
- 17 September 2026
- Study design
- Randomized controlled trial
- Evidence level
- Level 1, High (CEBM 1b)
- Authors
- Rodrigo Jover, Michael Bretthauer, Joaquin Cubiella, Sarah J E Barry, Anna Macios, Lauren Barnett, et al.
- PMID
- 42748427
- DOI
- 10.1056/NEJMoa2603816
Why clinicians should know about it
- Picked for Gastrointestinal and Colorectal Surgery (top studies of the week, 20 September 2026): Colonoscopy surveillance intervals after adenoma removal
- Picked for Gastroenterology (top studies of the week, 20 September 2026): 5-year surveillance noninferior to 3-year for cancer incidence
- Picked for Surgery (top studies of the week, 20 September 2026): Randomised trial, colonoscopy surveillance intervals
Abstract
BACKGROUND: More evidence is needed to inform recommendations for intervals of colonoscopy surveillance after polyp removal. METHODS: In this ongoing noninferiority trial conducted in eight European countries, we randomly assigned patients with high-risk adenomas (defined as ≥1 adenoma with a diameter of ≥10 mm, high-grade dysplasia, or villous growth or 3 to 10 adenomas of any kind) to undergo a first colonoscopy at 5 years after polyp removal or at 3 years; surveillance at 3 years is currently recommended in guidelines. The 3-year group also underwent colonoscopy at 5 years. The primary end point is the cumulative incidence of colorectal cancer at 10 years, with a prespecified noninferiority margin of 0.7 percentage points for the upper boundary of the confidence interval for the difference between the two groups. Here, we report the results of an interim analysis conducted after 5.5 years of follow-up. Inverse probability weighting was used to account for missing data owing to nonparticipation in surveillance colonoscopy at 5 years. In this analysis, the incidence of colorectal cancer is reported with a one-sided 99.12% confidence interval; for the final analysis at 10 years, the plan is to calculate a 95.33% confidence interval to maintain an overall type I error of 5%. RESULTS: A total of 10,799 patients underwent randomization: 5398 patients were assigned to the 5-year group and 5401 to the 3-year group. The 5-year cumulative incidence of colorectal cancer was 0.77% with less-frequent surveillance and 0.82% with more-frequent surveillance (difference, -0.05 percentage points); the upper boundary of the 99.12% confidence interval was 0.68, which met the criterion for noninferiority. The distribution of cancer stage at diagnosis did not appear to differ substantially between the two groups. A total of 5 patients died of colorectal cancer: 3 patients (0.06%) in the 5-year group and 2 (0.04%) in the 3-year group. CONCLUSIONS: In this interim analysis of a 10-year noninferiority trial, beginning surveillance colonoscopy at 5 years after polyp removal was noninferior to beginning at 3 years with respect to the cumulative incidence of colorectal cancer at 5 years among patients with high-risk adenomas. (Funded by the Research Council of Norway and others; EPoS II ClinicalTrials.gov number, NCT02319928.).
Abstract as published, via PubMed.
For healthcare professionals. The summary is generated by AI from the published abstract, and the evidence level is assigned automatically from the study design on the Oxford CEBM hierarchy. Neither is medical advice. Read the full paper before changing practice.