Neuroendocrine tumor of the common bile duct: a case report and review of the literature.

We report a rare case of neuroendocrine tumor (NET) in the common bile duct (CBD). The patient is a 56-year-old female who presented to our department with symptoms of fever but without jaundice. A preoperative examination showed a tumor in the CBD. The tumor volume was almost 5.5 × 4.5 × 4 cm3, which is the biggest NET in the CBD reported on PubMed. The imaging results (computed tomography [CT] and magnetic resonance imaging [MRI]) were not consistent with CBD adenocarcinoma. The tumor appeared to oppress the growth of the CBD rather than originate in the bile duct wall; combined with the low blood bilirubin index and lack of jaundice symptoms, the preoperative diagnosis was not clear. We performed a radical resection of the cholangiocarcinoma. The patient recovered well before going home. The pathology was NET (Grade 2). The patient showed no recurrence to date, without intravenous chemotherapy (8 months).