Cross AJ, Robbins EC, Pack K, et al. - This evaluation of the 2020 UK post-polypectomy surveillance guidelines revealed that these guidelines allow precise classification of post-polypectomy cases into those carrying a high risk for colorectal cancer (CRC) development, for whom one surveillance colonoscopy seems suitable, and those at low risk who can be managed via non-invasive screening.

• Colonoscopy surveillance intends to decrease CRC incidence post-polypectomy.

• The 2020 UK post-polypectomy surveillance guidelines were evaluated in this retrospective study of patients who had colonoscopy and polypectomy mostly between 2000 and 2010 at 17 UK hospitals, observed through 2017.

• In 21,318 cases, 368 CRCs occurred during the observation period (median: 10.1 years).

• Age ≥55 years, ≥2 premalignant polyps (PMPs), adenomas with tubulovillous/villous/unknown histology or high-grade dysplasia, proximal polyps and a baseline visit spanning 2–90 days were the baseline CRC risk factors identified.

• Relative to the general population, a higher CRC incidence without surveillance was noted in those with adenomas with high-grade dysplasia (standardized incidence ratio SIR: 1.74) or ≥2 PMPs, of which ≥1 was advanced (1.39).

• SIRs without surveillance were 0.75 and 1.30, respectively, for low-risk (71%) and high-risk (29%) patients; the SIR was 1.22 for high-risk patients post-first surveillance.