Cold snare polypectomy versus cold forceps biopsy in endoscopic treatment of colonic small and diminutive polyps - the effectiveness and safety in real world

The practice of colonoscopy is used to reduce the risk of colonic malignancy. Complete removal of polyps is required to prevent tumor recurrence and the development of potential interval cancers. However, it is difficult to completely remove the polyp that is more than 4 mm in size through cold forceps biopsy. Polypectomy with a cold snare has been increasingly utilized in recent years, which provides a chance of complete removal of the polyp. This study compares the effectiveness and safety between cold snare polypectomy (CSP) and cold forceps biopsy (CFB) in diminutive or small sessile polyp removal. Between August 2015 and June 2016, 164 consecutive patients with colorectal polyps <10 mm in size were enrolled into either the CSP or CFB group. Demographic data, the duration of colonoscopy withdrawal time, adverse events, and pathological reports were recorded. The primary outcome is complete polyp eradication histologically. The secondary outcomes include rates of adverse events and time taken for the procedures. Of 164 patients, 84 patients were in CSP group and 80 patients in CFB group. The CSP group comprised elder patients (P = 0.042), most of who were male (P = 0.359). There was no significant difference of indications for colonoscopy. The mean withdrawal time was significantly longer in the CSP group (12.5 +/- 6.90 minutes vs 9.14 +/- 5.45 minutes; P < 0.01). The mean polyp size was bigger in the CSP group (5.05 +/- 2.72 mm vs 3.84 +/- 1.52 mm, P < 0.05). Eighty-nine (84.7%) adenomas, 13 (12.4%) hyperplastic polyps, and three other polyps (2.9%) were resected in the CSP group. No high-grade dysplasia or malignancy was found. Pathological examination showed that 54 polyps were completely removed in CSP group. Thirteen polyps were not removed completely, and 38 polyps could not be surveyed due to tissue destruction during the procedure. In the CFB group, no polyps could be identified with complete removal. The complete histological polyp eradication rate is higher in the CSP group (51.4% vs 0%, P < 0.01). Under operator's discretion, 23 cases with 31 hemoclips were applied for bleeding prevention in the CSP group and only one in the CFB group. However, no further treatment requirement or delayed bleeding event was found in both groups. CSP is an effective method in small or diminutive polyps compared with CFB, and its safety is not inferior to CFB. Given these results and the high prevalence of such polyps, CSP is advocated as an alternate treatment.