Treatment for superficial non-ampullary duodenal epithelial tumors.

Because of the low prevalence of non-ampullary duodenal epithelial tumors (NADETs), standardized clinical management of sporadic superficial NADETs, including diagnosis, treatment, and follow-up, has not yet been established. Retrospective studies have revealed certain endoscopic findings suggestive of malignancy. Duodenal adenoma with high-grade dysplasia and mucosal cancer are candidates for local resection by endoscopic or minimally invasive surgery. The use of endoscopic treatment including endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD), for the treatment for superficial NADETs is increasing. EMR requires multiple sessions to achieve complete remission and repetitive endoscopy is needed after resection. ESD provides an excellent complete resection rate, however it remains a challenging method, considering the high risk of intraoperative or delayed perforation. Minimally invasive surgery such as wedge resection and pancreas-sparing duodenectomy are beneficial for superficial NADETs that are technically difficult to remove by endoscopic treatment. Pancreaticoduodenectomy remains a standard surgical procedure for treatment of duodenal cancer with submucosal invasion, which presents a risk of lymph node metastasis. Endoscopic or surgical treatment outcomes of superficial NADETs without submucosal invasion are satisfactory. Establishing an endoscopic diagnostic tool to differentiate superficial NADETs between adenoma and cancer as well as between mucosal and submucosal cancer is required to select the most appropriate treatment.