Impact of margin ablation after EMR of large nonpedunculated colonic polyps in routine clinical practice

Background and aims: Owing to its simplicity, effectiveness, and safety, EMR is the preferred treatment for the majority of large (>20 mm) nonpedunculated colonic polyps (LNPCPs); however, residual and recurrent ade-nomas (RRAs) encountered during surveillance constitute a major limitation. Thermal ablation of the post-EMR mucosal defect margin has been shown to be highly efficacious in reducing RRA in a randomized trial setting, but data on effectiveness in clinical practice are scarce. We aimed to determine the effectiveness of this technique for reducing RRAs in routine clinical practice. Methods: We analyzed data collected in 3 hospitals in Israel: Prospective data were available in 2 hospitals where margin thermal ablation with snare-tip soft coagulation (STSC) is routinely performed after EMR of LNPCP (TA-EMR). Only retrospective data were available from the third center, which exclusively did not perform STSC (standard EMR] [S-EMR]), during the study period. Surveillance was performed 4 to 6 months after resection. RRA was assessed endo-scopically with high-definition white light and optical chromoendoscopy. The primary endpoint was RRA at first sur-veillance colonoscopy. Results: Data from 764 patients with 824 LNPCPs were analyzed. The patient and lesion characteristics were similar between the groups. Four hundred sixty-four LNPCPs were treated by TA-EMR and 360 LNPCPs by S-EMR. RRA at first surveillance colonoscopy was detected in 14 (3.6%) of lesions in the TA-EMR group compared with 96 (31.6%) in the S-EMR group (P < .001; RR Z .14; 95% CI, .07-.29). Adverse events were comparable between the 2 groups. Conclusion: TA-EMR leads to a significant reduction in post-EMR recurrence in routine clinical practice.