Background and Aim: Endoscopic mucosal resection (EMR) with a cold snare is gaining increasing acceptance as an effective therapy for large, laterally spreading lesions in the colon. The cold snare technique offers a favorable risk profile, with low rates of bleeding, perforation, and post-procedure pain compared with the more widely used hot snare EMR technique. While there is increasing acceptance of cold snare EMR for the removal of medium (10–19 mm) and large (≥20 mm) sessile serrated lesions (SSLs), concerns remain about its suitability for the removal of similar sized adenomas. We aimed to study the differences in safety and efficacy of cold snare EMR for adenomas compared with SSLs.

Methods: Data were collected retrospectively for EMR procedures of Paris IIa SSLs and adenomas performed at a single center between 1 February 2018 and 30 June 2020. The Provation endoscopy reporting program and ieMR electronic medical record system were used to source size, morphology, method of resection, and recurrence data. Complications were captured through a review of medical records that included a 1-month follow-up phone call.

Results: A total of 144 eligible EMR procedures were performed over the study period. The SSLs and adenomas were similarly located throughout the colon. The adenoma group consisted of 54 tubular adenomas and 6 tubulovillous adenomas. There were 133 patients who completed their 6-month surveillance colonoscopy (SC1), and 62 had their 18-month surveillance colonoscopy (SC2) (Table 1). The overall recurrence rate at SC1 was considerably higher in the adenoma group (14% vs 2.6%; odds ratio [OR], 6.0; P = 0.027). The difference was most appreciable in lesions ≥20 mm (17.5% vs 2.6%; OR, 7.8; P = 0.06), with no significant difference in those sized 10–19 mm (5.9% vs 2.6%; OR, 2.3; P = 0.56). Recurrence was treated endoscopically in all cases. There were no complications reported in either group.

Conclusion: Our study shows both safety and efficacy of the cold snare technique for medium and large SSLs, while raising concerns about efficacy, but not safety, for similarly sized adenomas. It is reassuring that recurrence could be treated endoscopically in all cases. Considering this, and the impressive safety profile of the cold EMR technique, it may still be a suitable therapeutic option for medium and large adenomas, particularly in select high-risk patients. Further research is required to understand the reasons for the increased recurrence and to determine the optimal technique for cold snare EMR of adenomas.