Primary small cell carcinoma of the middle bile duct

We report a case of small cell carcinoma of the extrahepatic bile duct in an 80-year-old man who was initially admitted for malaise and jaundice. Cholangiography revealed stenosis at the middle of the extrahepatic bile duct. CT revealed a slightly high-density mass, 25 mm in diameter, in the middle of the extrahepatic bile duct, and biopsy from this lesion identified class IV. These findings led to a diagnosis of middle bile duct cancer, after which a pylorus-preserving pancreaticoduodenectomy was performed. Microscopic examination of the tumor showed small atypical cells with round or oval nuclei, and immunological staining was positive for synaptophysin, chromogranin A, and CD56. These findings were consistent with the diagnosis of small cell carcinoma. The postoperative course was uneventful, and the patient was discharged on postoperative day 32. However, multiple liver metastases were detected on CT at 4 months after surgery, thus chemotherapy consisting of cisplatin and etoposide was employed. Small cell carcinoma of the bile duct is rare, and its prognosis is generally poor, and there is no consensus on the course of postoperative treatment at present.