Extended cold snare polypectomy for small colorectal polyps increases the R0 resection rate.

Background and study aims:  Despite widespread use of cold snare polypectomy (CSP), the R0 resection rate is not well documented. We perform extended CSP, resecting polyps with a > 1 mm circumferential margin. The aim of this study is to compare the R0 resection rate of extended CSP with conventional CSP and to assess safety.

Patients and methods : From April 2014 to September 2016, 712 non-pedunculated colorectal polyps, < 10 mm in size, resected using CSP from 316 patients were retrospectively analyzed.

Results:  We divided lesions into conventional CSP (n = 263) and extended CSP groups (n = 449). The baseline characteristics of these two groups were not significantly different in univariate or multivariate analyses. Sessile polyps comprised 94 % (668/712), and the remaining were flat-elevated polyps. Mean size of polyps (±standard deviation) was 4.2 ± 1.5 mm. The most frequent pathology was low grade adenoma (97 %, 689/712). The R0 resection rate was significantly higher in the extended CSP group (439/449 [98 %]) than in the conventional CSP group (222/263 [84 %], P  < 0.001). There was no delayed bleeding or perforation in either group (conventional CSP group, 0/263, 95 % confidence interval: 0.0 - 1.4 % and extended CSP group, 0/449, 95 % confidence interval: 0.0 - 0.8 %).

Conclusions:  Extended CSP results in a higher R0 resection rate compared with conventional CSP. Extended CSP did not result in a higher rate of delayed bleeding or perforation. Extended CSP is a safe and promising procedure for endoscopic resection of non-pedunculated colorectal polyps < 10 mm in size.