S395 Cold vs Hot Snare Endoscopic Mucosal Resection for Large Nonpedunculated Colorectal Polyps: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Introduction: Endoscopic mucosal resection (EMR) is pivotal in managing large nonpedunculated colorectal polyps (LNPCPs). While hot snare EMR (HS-EMR) is traditionally favored for its lower recurrence rates, cold snare EMR (CS-EMR) has attracted interest due to its superior safety profile. We aimed to compare CS-EMR and HS-EMR in terms of efficacy and safety outcomes for the removal of LNPCPs. Methods: We systematically searched PubMed, Embase, and Cochrane databases through February 2025 to identify randomized controlled trials comparing CS-EMR with HS-EMR in LNPCPs. Recurrence rate and safety profile were the outcomes of interest. Data were pooled using random-effects models with subgroup analyses based on polyp size and histologic subtype. Results: Four studies were included in the meta-analysis. Of these, 3 were full-text articles and one was an abstract. Three studies examined colorectal polyps larger than 20 mm, while 1 study included polyps larger than 15 mm. In this study, the median polyp size was 30 mm (interquartile range 25-35). A total of 1,429 patients and 1,516 polyps were included. Of these, 722 patients (50.5%) and 766 polyps (50.5%) underwent CS-EMR. The risk of recurrence in the CS-EMR was significantly higher (≥15 mm: risk ratio [RR] 2.02, 95% confidence interval [CI] 1.44-2.84; ≥20 mm: RR 1.91, 95% CI 1.50-2.43). The subgroup including adenomatous polyps showed similar trends (≥15 mm: RR 2.05, 95% CI 1.38-3.03; ≥20 mm: RR 1.93, 95% CI 1.49-2.50), whereas the risk of recurrence in sessile serrated polyps (SSP) did not differ significantly (≥20 mm: RR 2.00, 95% CI 0.59-6.79). Safety outcomes favored CS-EMR, with lower risks of perforation (RR 0.11, 95% CI 0.02-0.63), postprocedural bleeding (RR 0.34, 95% CI 0.13–0.88), and clip closure (RR 0.35, 95% CI 0.16-0.78), while intraprocedural bleeding (RR 0.58, 95% CI 0.30-1.10) and postpolypectomy syndrome (RR 0.60, 95% CI 0.24-1.46) were similar. Conclusion: Our meta-analysis shows that CS-EMR offers a safer profile with significantly lower perforation and postprocedural bleeding rates in the removal of LNPCPs. As for the recurrence risk, it is higher with CS-EMR compared to HS-EMR for the large nonpedunculated adenomatous polyps, while it did not reach statistical significance for sessile serrated polyps. These findings support current guidelines favoring HS-EMR for large nonpedunculated adenomatous polyps while highlighting that CS-EMR may be a viable alternative in select clinical scenarios.