Background and study aims: Surveillance guidelines are equivocal on the necessity of early surveillance colonoscopy (ESC) after piecemeal endoscopic mucosal resection (pEMR) of 10-20mm non-pedunculated colorectal polyps (NPCPs). This study aimed to assess recurrence rates and associated factors at ECS following pEMR of 10-20mm NPCPs.
Patients and methods: A retrospective, multicenter cohort study was performed at five hospitals in The Netherlands. Patients who underwent pEMR of NPCPs sized 10-20mm between 2014 and 2021 and were referred for ESC (range: 3-9 months) were included. The primary outcome was recurrence rate at ESC. Secondary outcomes included scar identification rates, both overall and of tattooed sites. A mixed-effects model was used to identify associated factors with recurrence.
Results: A total of 389 patients with pEMR of 426 NPCPs sized 10-20mm (median: 15mm, interquartile range: 13-20mm) were included. Overall, 262/426(62%; 95% confidence interval (CI): [57-66]) scars were identified at ESC, increasing to 82% of tattooed sites. The overall recurrence rate was 35/426(8.2%; 95%CI [6.0-11.2]), and 35/262(13.4%; 95%CI [9.8-18.0]) when the scar was identified. Median recurrence size was 5mm, without high-grade dysplasia. No NPCP characteristics were associated with recurrence.
Conclusions: This real-world study found a substantial recurrence rate at ESC following pEMR of 10-20mm NPCPs. ESC scar identification was moderate but improved with tattoo placement. Although early surveillance could be considered to avoid missing recurrences, the small recurrence size and absence of high-grade dysplasia suggest that modestly extending the interval beyond that of our study may still allow timely detection of recurrences and metachronous lesions.
