Spindle cell-type
undifferentiated carcinoma arising from the extrahepatic bile duct is extremely rare. We herein report a case of this type of
carcinoma in the common bile duct of the hepatic hilus. A 59-year-old man was admitted to our hospital complaining of
jaundice. The laboratory data revealed an elevation of the serum
carbohydrate antigen 19-9 level. Cholangiography revealed a complete obliteration of the left hepatic bile duct and
stenosis of the bile duct from the superior to the right hepatic bile duct. Computed tomography showed the
tumor to measure 15 x 12 mm in the hepatic hilus, with the obliteration of the right to main trunk of the portal vein and a swollen lymph node in the hepato-duodenum ligament. Arteriography revealed a kink of the right hepatic artery; therefore an encasement of the right hepatic artery was suspected. We preoperatively diagnosed hilus bile duct
carcinoma and scheduled a right trisection
hepatectomy. Intraoperative frozen sections taken from the
tumor and tissues around the hepatic arteries showed spindle and inflammatory cells; therefore an
inflammatory pseudotumor was diagnosed intraoperatively. As the right hepatic bile duct was occluded, a right lobe
hepatectomy was performed. However, a permanent section revealed both spindle cells and poorly differentiated
tubular adenocarcinoma cells positive for
CAM5.2, AE1/AE3, and
vimentin. On the basis of these findings, the
tumor was finally diagnosed to be spindle cell-type
undifferentiated carcinoma. Unfortunately, the patient died of
pulmonary infarction 11 days after the operation.