Current Management of Duodenal Neoplasia: Endoscopic Treatment for Large Superficial Non-Ampullary Duodenal Epithelial Tumor.

Background: Superficial non-ampullary duodenal epithelial tumors (SNADETs) were previously considered rare. However, the widespread use of health checkup endoscopy, improvements in endoscopic imaging and heightened awareness of SNADETs among endoscopists have recently led to an increase in their detection rate. Particularly for large SNADETs, the possibility of including cancer must be considered, and thus, complete and reliable resection is essential. Although surgical resection has traditionally been the standard treatment, its high invasiveness has led to increased interest in less invasive endoscopic treatments. Nevertheless, due to the unique anatomical and physiological features of the duodenum, endoscopic treatment in the duodenum remains highly challenging and presents many technical difficulties.

Summary: This review provides a comprehensive overview of current endoscopic treatment options for large SNADETs, including conventional endoscopic mucosal resection (C-EMR), underwater endoscopic mucosal resection (U-EMR), cold snare endoscopic mucosal resection (CS-EMR), endoscopic submucosal dissection (ESD), and laparoscopic-endoscopic cooperative surgery, incorporating the latest clinical findings. While C-EMR, U-EMR, and CS-EMR are associated with lower technical difficulty and favorable safety, they tend to show lower en bloc resection rates and higher recurrence rates for large SNADETs when compared to ESD. In contrast, ESD offers higher en bloc resection rates but carries a greater risk of complications due to its technical complexity. To overcome these limitations, several techniques have been developed, such as the pocket-creation method, water pressure method, improved closure strategies for mucosal defects, and drainage with endoscopic nasobiliary and pancreatic drainage to prevent exposure to pancreatic juice and bile.

Key messages: Multiple endoscopic strategies are available for the treatment of large SNADETs. However, due to the rarity of the disease and variation in institutional expertise, a standardized treatment strategy has not yet been established. Endoscopic treatment for large SNADETs is technically very challenging and carries a high risk. Therefore, careful consideration of the indication for each treatment method, along with a full understanding of their respective advantages and disadvantages, is essential. In recent years, the safety of endoscopic resection has been gradually improving due to various technical innovations and better management of adverse events, making ESD, which offers a high en bloc resection rate, an increasingly reasonable treatment option.