S351 Comparison of Underwater Cold Snare Polypectomy and Conventional Cold Snare Polypectomy for Small Size Colorectal Lesions <10 mm: Meta-Analysis of Randomized Controlled Trials

Introduction: Cold snare polypectomy (CSP) has been reported as safe and effective method for the removal of small colorectal polyps. However, some studies showed low R0 resection rate and higher incomplete resections. Underwater cold snare polypectomy (U-CSP) is a novel technique. We conducted a meta-analysis of randomized controlled trails (RCTs) to evaluate comparative outcomes of U-CSP and conventional CSP in small size colorectal lesions <10 mm. Methods: Several databases were reviewed from inception to May 18, 2025, to identify RCTs comparing the outcomes of U-CSP vs conventional CSP in small colorectal lesions. Our outcomes of interest were en bloc resection, R0 resection, perforation, bleeding, and mean resection time. We calculated risk ratios (RRs) with 95% confidence interval (CI) for categorical variables and mean differences with 95% CI for continuous variables. Data was analyzed using the random effect model. Heterogeneity was assessed using I2 statistics. Results: We included 4 RCTs with 757 patients (U-CSP 383, conventional CSP 374) in our analysis. The mean age of the patients was 60 (3.1) years. U-CSP was associated with higher rates of R0 resection, RR (95% CI): 1.17 (1.03, 1.33) P = 0.01, I2 83%. We found no significant difference in rates of en bloc resection, RR (95% CI): 0.99 (0.97, 1.01) P = 0.44, I2 25%, bleeding, RR (95% CI): 0.54 (0.18, 1.65) P = 0.28, I2 18%, and mean resection time (seconds), MD (95% CI): 0.21 (-12.04, 12.46) P = 0.97, I2 94%. No case of perforation was reported in each group. Conclusion: Our meta-analysis demonstrates that U-CSP is associated with higher rates of R0 resection as compared to conventional CSP in small size colorectal lesions <10 mm. Future multicenter studies are needed to validate these findings further.