Published online Dec 7, 2022. doi: 10.3748/wjg.v28.i45.6397
Peer-review started: July 30, 2022
First decision: September 2, 2022
Revised: September 14, 2022
Accepted: October 19, 2022
Article in press: October 19, 2022
Published online: December 7, 2022
Processing time: 125 Days and 0.9 Hours
The optimal method to remove sessile colorectal lesions sized 10-20 mm remains uncertain. Piecemeal and incomplete resection are major limitations in current practice, such as endoscopic mucosal resection (EMR) and cold or hot snare polypectomy. Recently, EMR with circumferential precutting (EMR-P) has emerged as an effective technique, but the quality of current evidence in comparative studies of conventional EMR (CEMR) and EMR-P is limited.
To investigate whether EMR-P is superior to CEMR in removing sessile colorectal polyps.
This multicenter randomized controlled trial involved seven medical institutions in China. Patients with colorectal polyps sized 10-20 mm were enrolled and randomly assigned to undergo EMR-P or CEMR. EMR-P was performed following submucosal injection, and a circumferential mucosa incision (precutting) was conducted using a snare tip. Primary outcomes included a comparison of the rates of en bloc and R0 resection, defined as one-piece resection and one-piece resection with histologically assessed clear margins, respectively.
A total of 110 patients in the EMR-P group and 110 patients in the CEMR group were finally evaluated. In the per-protocol analysis, the proportion of en bloc resections was 94.3% [95% confidence interval (CI): 88.2%-97.4%] in the EMR-P group and 86% (95%CI: 78.2%-91.3%) in the CEMR group (P = 0.041), while subgroup analysis showed that for lesions > 15 mm, EMR-P also resulted in a higher en bloc resection rate (92.0% vs 58.8% P = 0.029). The proportion of R0 resections was 81.1% (95%CI: 72.6%-87.4%) in the EMR-P group and 76.6% (95%CI: 68.8%-84.4%) in the CEMR group (P = 0.521). The EMR-P group showed a longer median procedure time (6.4 vs 3.0 min; P < 0.001). No significant difference was found in the proportion of patients with adverse events (EMR-P: 9.1%; CEMR: 6.4%; P = 0.449).
In this study, EMR-P served as an alternative to CEMR for removing nonpedunculated colorectal polyps sized 10-20 mm, particularly polyps > 15 mm in diameter, with higher R0 and en bloc resection rates and without increasing adverse events. However, EMR-P required a relatively longer procedure time than CEMR. Considering its potential benefits for en bloc and R0 resection, EMR-P may be a promising technique in colorectal polyp resection.
Core Tip: The optimal method for removal of sessile colorectal lesions sized 10-20 mm remains uncertain. Piecemeal and incomplete resection are major limitations of conventional endoscopic mucosal resection (CEMR) in removing sessile colorectal polyps. In this study, we found that endoscopic mucosal resection with circumferential precutting achieved better en bloc resection (94.3% vs 86.0%; P = 0.041) with no increase in adverse events, and can serve as an alternative technique to CEMR in the removal of sessile colorectal lesions sized 10-20 mm.