High-Risk Adenomas: Can Surveillance Colonoscopy Wait 5 Years Instead of 3?: NEJM | September 2026

What Did the Study Find?

The EPoS trial randomized 10,799 patients with high-risk adenomas to first surveillance colonoscopy at 5 years or 3 years after polypectomy.

At 5 years, cumulative colorectal cancer incidence was 0.77% with 5-year vs 0.82% with 3-year surveillance.

The absolute difference was −0.05 percentage points, meeting the prespecified criterion for noninferiority.

Cancer stage at diagnosis appeared similar between strategies.

CRC mortality was extremely low: 3 vs 2 deaths, respectively.

Importantly, these are interim results from an ongoing 10-year trial; the primary endpoint remains 10-year CRC incidence.

High-risk adenomas included lesions ≥10 mm, high-grade dysplasia, villous histology, or 3–10 adenomas.

Why Does It Matter?

Three-year surveillance after high-risk adenoma removal generates a substantial colonoscopy burden. Extending the interval could reduce procedures without increasing early CRC incidence.

GastroAGI Takeaway

Five years may be enough—but it is too early to rewrite surveillance guidelines. These large randomized data are highly reassuring, but the definitive question is 10-year CRC incidence. For now, this is potentially practice-changing evidence awaiting final follow-up.