LAUSR

Preoperative biopsies are required to diagnose superficial duodenal epithelial tumours because a non-invasive endoscopic method for accurate diagnosis has not been established. However, biopsies cause scarring of the lesion. Kinoshita et al. reported that 24.6% of the duodenal lesions considered applicable for conventional endoscopic mucosal resection (C-EMR) were treated by endoscopic submucosal dissection (ESD) because of a non-lifting sign caused by biopsies 1 . However, duodenal ESD is challenging, even for experts 2 . Underwater EMR (UEMR) is a recently developed technique considered as easy and safe for resecting fibrotic colorectal polyps and small duodenal adenomas 3-5 . This article is protected by copyright. All rights reserved.