表在性非乳頭部十二指腸上皮性腫瘍に対する内視鏡的切除術の現状と課題

Superficial non-ampullary duodenal epithelial tumors (SNADET) are increasingly being detected and treated in recent years. In view of the high invasiveness of pancreaticoduodenectomy, endoscopic resection (ER) is being accepted for treatment of SNADET. However, duodenal ER is occasionally technically challenging owing to submucosal fibrosis secondary to biopsy performed before treatment. Underwater endoscopic mucosal resection involves filling of the duodenal lumen with water or saline and resection of the lesion using a snare without submucosal injection. Cold polypectomy is useful to resect target lesions physically without the use of radiofrequency current and may serve as a safe and simple method for SNADET, although the resectability rate of this technique may be insufficient. Endoscopic submucosal dissection of SNADET is technically challenging and is associated with a significantly high risk of delayed adverse events. However, recent reports describe novel techniques, such as the water pressure and pocket creation methods, which are associated with improved outcomes. Furthermore, closure of the mucosal defect after resection is shown to significantly reduce the rate of delayed adverse events after duodenal ER. Further studies are warranted to clarify the curative criteria, long-term results, and appropriate surveillance methods.