Current Challenge: Endoscopic Submucosal Dissection of Superficial Non-ampullary Duodenal Epithelial Tumors

With the widespread use of esophagogastroduodenoscopy in recent years, the detection rate of superficial non-ampullary duodenal epithelial tumors (SNADETs) is increasing. Most SNADETs are early-stage adenocarcinoma or benign conditions, including adenoma. Therefore, endoscopic resection is desirable from the perspective of quality of life. However, endoscopic resection for SNADETs has not yet been established. Endoscopic submucosal dissection (ESD) is the most promising method for the treatment of SNADETs, because ESD provides a high rate of en bloc resection and a low rate of recurrence regardless of the tumor size. However, the difficulty of the procedure and a high rate of severe adverse events including perforation and bleeding have become major problems. Various preventive countermeasures for adverse events, such as use of specific devices, endoscope stabilization methods, and endoscopic closure of the post-ESD ulcer using clips, are reported to reduce the risk of the adverse events of ESD for SNADETs. This article reviews and highlights the current state of ESD for SNADETs and new challenges towards safe and effective ESD.