Underwater endoscopic submucosal dissection with pocket method and an additional working channel: from traction to closure

Endoscopic submucosal dissection (ESD) is a safe and effective technique that allows en bloc resection of rectal neoplasia 1. Several traction methods and dedicated devices have been developed to improve submucosal exposure, increase the dissection speed, and potentially reduce adverse events 2 3 4. A 53-year-old man with no relevant medical history was referred for ESD of a 20 mm rectal laterally spreading tumor, granular homogeneous type, without endoscopic signs of invasive cancer (Fig. 1). The procedure was performed in an underwater setting using the pocket technique as the primary dissection strategy, ensuring stable and controlled submucosal access (Video 1). Within this framework, the AWC played a pivotal role by allowing the introduction of a foreign body grasping forceps into the submucosal tunnel, providing effective countertraction and improved visualization of the dissection plane, thereby facilitating a faster and more controlled dissection (Fig. 2). After the completion of the resection, the same foreign body grasping forceps inserted through the AWC was used to approximate the resection margins, enabling the precise and efficient placement of through-the-scope clips for defect closure (Fig. 3). The patient was discharged on the same day under good clinical conditions. Histological examination revealed a tubulovillous adenoma with low-grade dysplasia and R0 resection. This case highlights how the AWC can enhance standard ESD techniques by supporting both effective traction within the submucosal tunnel and controlled closure of the resection defect. This simple and cost-efficient approach represents a practical alternative to more complex traction systems and emerging endoscopic robotic platforms. EndoscopyUCTNCodeTTT₁AQ₂AC Article published online: 17 February 2026 © 2026. The Author (s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution License, permitting unrestricted use, distribution, and reproduction so long as the original work is properly cited. (https: //creativecommons. org/licenses/by/4. 0/). Georg Thieme Verlag KG Oswald-Hesse-Straße 50, 70469 Stuttgart, Germany