Comparing underwater endoscopic submucosal dissection and conventional endoscopic submucosal dissection for large laterally spreading tumor: a randomized controlled trial (with video)

Colorectal endoscopic submucosal dissection (ESD) is challenging despite its usefulness. Underwater ESD (UESD) provides better traction and a clearer view of the submucosal layer than conventional ESD (CESD). This study compared the efficiency of UESD and CESD for large (20-50 mm) laterally spreading tumor (LST).