[A Case of Pancreatoduodenectomy for Multiple Nonfunctioning Neuroendocrine Tumors of the Duodenum].

A 42-year-old woman was referred to our hospital because of incidentally discovered multiple neoplastic lesions of the duodenum. Upper gastrointestinal endoscopy showed there were more than 10 submucosal tumors and less than 10 mm in diameter. Histological examination of the biopsy specimen revealed nonfunctioning neuroendocrine tumor(NET). Enhanced computed tomography(CT)showed neither regional lymph node nor distant metastasis, so we performed pancreatoduodenectomy with regional lymph node dissection. Pathological examination showed multiple NET G2 less than 5 mm in size with invasion to muscularis propria and 3 lymph node metastases, so diagnosed as pT2(m)N1M0, Stage Ⅲ. She is alive without tumor recurrence for 14 months after surgery. In general, sporadic nonfunctioning NET of the duodenum less than 10 mm in diameter has low possibility of lymph node metastasis. However, our case suggested the possibility of lymph node metastasis in patients with multiple NETs of the duodenum, in spite of small size. Therefore, pancreatoduodenectomy with regional lymph node dissection should be considered for multiple nonfunctioning NETs of the duodenum.