Cold versus hot endoscopic mucosal resection for nonpedunculated colorectal polyps sized 6–10 mm: a randomized trial
submitted 08 May 2017
accepted after revision 04 August 2017
12 September 2017 (eFirst)
Background and study aims Cold snare polypectomy is an established method for the resection of small colorectal polyps; however, significant incomplete resection rates still leave room for improvement. We aimed to assess the efficacy of cold snare endoscopic mucosal resection (CS-EMR), compared with hot snare endoscopic mucosal resection (HS-EMR), for nonpedunculated polyps sized 6 – 10 mm.
Patients and methods This study was a dual-center, randomized, noninferiority trial. Consecutive adult patients with at least one nonpedunculated polyp sized 6 – 10 mm were enrolled. Eligible polyps were randomized (1:1) to be treated with either CS-EMR or HS-EMR. Both methods involved submucosal injection of a methylene blue-tinted normal saline solution. The primary noninferiority end point was histological eradication evaluated by postpolypectomy biopsies (noninferiority margin – 10 %). Secondary outcomes included occurrence of intraprocedural bleeding, clinically significant postprocedural bleeding, and perforation.
Results Among 689 patients screened, 155 patients with 164 eligible polyps were included (CS-EMR n = 83, HS-EMR n = 81). The overall rate of histological complete resection was 92.8 % in the CS-EMR group and 96.3 % in the HS-EMR group (difference 3.5 %; 95 % confidence interval [CI] – 4.15 to 11.56), showing noninferiority of CS-EMR compared with HS-EMR. CS-EMR was shown to be noninferior both for polyps measuring 6 – 7 mm (CS-EMR 93.3 %; HS-EMR 100 %; 95 %CI – 7.95 to 21.3) and those of 8 – 10 mm (92.5 % vs. 94.7 %, respectively; 95 %CI – 7.91 to 13.16). Rates of intraprocedural bleeding were similar between the two groups (CS-EMR 3.6 %, HS-EMR 1.2 %; P = 0.30). No clinically significant postprocedural bleeding or perforation occurred in either group.
Conclusions CS-EMR appears to be a valuable modification of the standard cold snare technique, obviating the need to use diathermy for nonpedunculated colorectal polyps sized 6 – 10 mm.
Trial registered at ClinicalTrials.gov (NCT02678663).