# Comparing underwater and conventional cold snare polypectomy for colorectal adenomas: Prospective randomized controlled trial

## TL;DR

This study compares two methods for removing small colorectal polyps and finds that underwater cold snare polypectomy is more effective and safe.

## Contribution

The study provides new evidence that underwater cold snare polypectomy improves resection completeness for small colorectal adenomas.

## Key findings

- UCSP had significantly higher R0 resection rates compared to CSP.
- UCSP achieved higher muscularis mucosa resection rates than CSP.
- Operative time was similar between UCSP and CSP, with no major complications in either group.

## Abstract

In this study, we aimed to evaluate efficacy and safety of underwater cold snare polypectomy (UCSP) for treating colorectal adenoma.

This single-center, prospective, randomized controlled trial screened patients with colorectal adenomas measuring 4 to 9 mm in diameter that were identified through colonoscopies at the Department of Gastroenterology in Jianyang People’s Hospital between April 2022 and October 2023. Patients were randomly assigned to undergo UCSP or cold snare polypectomy (CSP). Both groups underwent narrow-band imaging to determine international colorectal endoscopic morphology of type 2 noncancerous lesions. Following polyp removal, biopsy specimens were collected from the base and margins to assess the completeness of resection.

The study included 227 polyps from 172 patients; median sizes in the UCSP (n = 122) and CSP groups (n=105) were 5 mm and 6 mm, respectively. The R0 (96.7% vs. 86.7%;
P
=0.005) and muscularis mucosa resection rates (68.9% vs. 43.8%;
P
<0.0001) were significantly higher in the UCSP group than in the CSP group. However, operative time for the UCSP group (109.5 s; 86.8–134.3 vs. 110.0 s; 83.5–143.5
P
=0.890) was not significantly longer than that for the CSP group. Neither group exhibited delayed bleeding or perforations.

UCSP has a high R0 rate for colorectal adenomas measuring 4 to 9 mm.