Gastroenterology Research, ISSN 1918-2805 print, 1918-2813 online, Open Access
Article copyright, the authors; Journal compilation copyright, Gastroenterol Res and Elmer Press Inc
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Original Article

Volume 19, Number 3, June 2026, pages 119-126

Efficacy and Safety of Underwater Versus Conventional Cold Snare Polypectomy for Small Colorectal Polyps: A Meta-Analysis of Randomized Controlled Trials

Figures

↓  Figure 1. Forest plot for en bloc resection.
Figure 1.
↓  Figure 2. Forest plot for R0 resection.
Figure 2.
↓  Figure 3. Forest plot for intraprocedural bleeding.
Figure 3.

Tables

↓  Table 1. Studies Characteristics
 
StudyCountryDesignPatientsPolyps (UCSP/CCSP)Size (mm)Snare (mm)
CCSP: conventional cold snare polypectomy; RCT: randomized controlled trial; UCSP: underwater cold snare polypectomy.
Myung et al, 2022South KoreaSingle-center RCT11098/1004–99
Zachou et al, 2024GreeceSingle-center RCT220198/1995–1010
Fu et al, 2025ChinaSingle-center RCT172122/1054–9Not reported

 

↓  Table 2. Histopathological Categorization of Resected Polyps by Study and Treatment Arm
 
Histological categoryUCSP, n (%)CCSP, n (%)
CCSP: conventional cold snare polypectomy; UCSP: underwater cold snare polypectomy.
Myung et al, 2022 (UCSP, n = 98; CCSP, n = 100)
  Tubular adenoma, low-grade dysplasia75 (76.5)75 (75.0)
  Tubular adenoma, high-grade dysplasia1 (1.0)0 (0.0)
  Sessile serrated lesion2 (2.0)5 (5.0)
  Hyperplastic polyp20 (20.4)20 (20.0)
Fu et al, 2025 (UCSP, n = 122; CSP, n = 105; P = 0.172)
  Adenoma, low-grade dysplasia118 (96.7)100 (95.2)
  Tubulovillous adenoma2 (1.6)0 (0.0)
  Adenoma, high-grade dysplasia2 (1.6)5 (4.8)
Zachou et al, 2024/COLDWATER (UCSP, n = 198; CCSP, n = 199; P = 0.31)
  Tubular adenoma101 (51.0)108 (54.3)
  Villous adenoma5 (2.5)8 (4.0)
  Tubulovillous adenoma63 (31.8)48 (24.1)
  Sessile serrated lesion29 (14.7)35 (17.6)

 

↓  Table 3. Risk of Bias Assessment
 
StudyRandomizationDeviationsMissing dataOutcome measurementSelective reporting
Myung et al, 2022LowSome concernsLowLowLow
Zachou et al, 2024LowLowLowLowLow
Fu et al, 2025LowSome concernsLowLowLow