Related Experiment Video
Updated: Aug 5, 2026

Evaluation of the Effectiveness of Longitudinal Incision for Endoscopic Submucosal Excavation of Gastric Subepithelial Lesions
Published on: April 28, 2026
Clinical Outcomes of Underwater Endoscopic Submucosal Dissection for Duodenal Tumors: A Systematic Review and
Kumiko Kirita1, Teppei Akimoto1, Yasunori Sato2
1Division of Research and Development for Minimally Invasive Treatment, Cancer Center Keio University School of Medicine, Tokyo, Japan.
Background And Study Aim:
Underwater endoscopic submucosal dissection (U-ESD) has recently been introduced as a technique that may improve visualization and submucosal layer expansion. However, the clinical outcomes of U-ESD for duodenal tumors have not been systematically evaluated. This study aimed to assess the efficacy and safety of U-ESD for duodenal tumors through a systematic review and meta-analysis.
Patients And Methods:
A comprehensive literature search was conducted using PubMed, Scopus, and the Cochrane Library from database inception to December 12, 2025. Studies evaluating U-ESD for duodenal tumors were included. Primary outcomes included en bloc resection, R0 resection, procedure time, adverse events, and complete mucosal defect closure. Pooled estimates were calculated using a random-effects model.
Results:
Four retrospective studies comprising 298 lesions treated with U-ESD were included. The pooled procedure time was 59 min (95% CI, 48-70 min; I2 = 72%). The pooled en bloc resection rate was 99% (95% CI, 97%-100%; I2 = 0%), and the pooled R0 resection rate was 89% (95% CI, 81%-93%; I2 = 54%). The pooled intraoperative perforation rate was 5% (95% CI, 1%-23%; I2 = 88%). The pooled delayed perforation and delayed bleeding rates were 1% (95% CI, 0%-3%; I2 = 0%) and 2% (95% CI, 1%-5%; I2 = 0%), respectively.
Conclusion:
Current evidence suggests that U-ESD is a feasible treatment option for duodenal tumors and is associated with favorable clinical outcomes. However, the available evidence remains limited, and potential biases and concerns regarding generalizability warrant cautious interpretation of these findings.
