A Case of Primary Small-cell Neuroendocrine Carcinoma in the Lower Bile Duct

Abstract

A 75-year-old man presented at a local clinic complaining of jaundice and was referred to our hospital for further investigation and treatment. Contrast-enhanced computed tomography (CECT) showed a 22-mm mass in the head of the pancreas and an elevated growth extending into the bile duct. Endoscopic retrograde cholangiopancreatography showed irregular stenosis of the lower bile duct and dilatation of the upper bile duct. Lower bile duct cancer was diagnosed, and subtotal stomach-preserving pancreatoduodenectomy was performed. Small-cell neuroendocrine carcinoma (NEC) was diagnosed on the basis of the histopathological findings. The patient's postoperative course was uneventful, and the patient was discharged on postoperative Day 27. Five courses of postoperative chemotherapy with cisplatin and irinotecan were administered, and as of 12 months after surgery, the patient is alive with no recurrence. Primary NEC of the bile duct is extremely rare, and its prognosis is extremely poor. The classification of NEC was amended in the WHO 2017/2019 editions, and since further investigations of multimodal treatment are required, this case is reported along with a short discussion of the literature.