Efficacy and safety of underwater ESD

AIM: to assess and compare the efficacy and safety of underwater endoscopic submucosal dissection (UESD) for superficial epithelial lesions of colon and cecum.

PATIENTS AND METHODS: twenty-six patients with 27 superficial epithelial lesions of the colon and cecum, indicated for monoblock removal, and removed by UESD at a single center were prospectively included in the study (2024– 2025). The primary end point was technical success, defined as macroscopic complete resection.

RESULTS: the resected tumor size was 32 ± 11.6 mm, operative time — 78.0 [49.0; 108.5] min, en bloc resection rate was 100% (27 lesions). R0 resection rate was 96.3% (26 lesions). There were no cases of delayed bleeding and perforation. One patient had postpolypectomy syndrome.

CONCLUSION: UESD is effective and safe strategy for colorectal lesions resection. These results require confirmation in further multicenter randomized trials.

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