Risk of total metachronous advanced neoplasia at surveillance colonoscopy after detection of serrated lesions: a matched case–cohort study.

To identify the non-serrated lesion group, the list of all patients who underwent endoscopy at CHUM was consulted systematically using year of index colonoscopy in the serrated lesion group as a starting point, and patients were matched consecutively according to the prespecified criteria. Patients with serrated lesions are likely to develop further clinically significant serrated lesions at follow-up, including high-risk serrated lesions, which are very rarely encountered in patients with only index conventional adenomas [12]. Overall, 10.3 % of patients in the serrated lesion group had metachronous advanced adenomas vs. 5.8 % in the non-serrated lesion group, and 13.5 % vs. 0.9 %, respectively, had metachronous high-risk serrated lesions (Table 2). Risk of total metachronous advanced neoplasia at surveillance colonoscopy after detection of serrated lesions: a matched case-cohort study. [Extracted from the article]