Cold Versus Hot Snare Endoscopic Mucosal Resection for Colorectal Polyps: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Endoscopic mucosal resection (EMR) is central to colorectal cancer prevention, but the optimal snare technique, cold versus hot, for achieving complete and safe resection remains debated.This systematic review and meta-analysis compared cold snare EMR (CS-EMR) with hot snare EMR (HS-EMR) across colorectal polyp sizes.PubMed, Scopus, and Web of Science were searched from inception to September 2026 for randomized controlled trials comparing CS-EMR with HS-EMR in adults undergoing colorectal polypectomy.Efficacy outcomes included en bloc resection and recurrent or residual adenoma.Safety outcomes included immediate and delayed bleeding, perforation, postpolypectomy syndrome, and any adverse event.Procedure duration was also assessed.Risk of bias was assessed using the Cochrane Risk of Bias 2 (RoB 2) tool.Risk ratios (RRs) and standardized mean differences (SMDs) were pooled using randomeffects models.Seven randomized controlled trials were included.En bloc resection rates were comparable between groups (RR: 0.91, 95% CI: 0.77-1.06,p = 0.22).CS-EMR was associated with a shorter procedure duration (SMD: -0.17, 95% CI: -0.33 to -0.02; p = 0.03) and a lower risk of perforation (RR: 0.10, 95% CI: 0.02-0.55).However, CS-EMR was associated with a higher risk of recurrent or residual adenoma (RR: 1.88, 95% CI: 1.43-2.48;p < 0.00001), an effect that appeared to be driven by trials involving large (≥20 mm) nonpedunculated polyps.No significant differences were observed in immediate bleeding (RR: 1.10, 95% CI: 0.51-2.35),delayed bleeding (RR: 0.46, 95% CI: 0.14-1.52),postpolypectomy syndrome (RR: 0.58, 95% CI: 0.23-1.47),or any adverse event (RR: 0.58, 95% CI: 0.28-1.22).CS-EMR was associated with shorter procedure duration and a lower risk of perforation, without significant differences in bleeding or overall adverse events, but was associated with a clinically significant increase in recurrent or residual adenoma, particularly in large nonpedunculated polyps.CS-EMR may therefore be a suitable option for small and intermediate-sized colorectal polyps, whereas its use in larger lesions should be accompanied by appropriate endoscopic surveillance.Further randomized trials with standardized recurrence definitions and longer follow-up are needed to clarify the optimal lesion-size thresholds for technique selection.