Carcinoma of the cystic duct protruding into the common bile duct: report of a case.

We report herein the case of 65-year-old man in whom a diagnosis of primary carcinoma of the cystic duct was made on the basis of Farrar's criteria. The patient was admitted with upper abdominal pain, and although there was no evidence of jaundice or a palpable mass, there was tenderness in his right upper quadrant. Carcinoma of the cystic duct was suspected on the basis of computed tomography and magnetic resonance imaging findings. Cholecystectomy with resection of the bile duct and lymph node resection was performed, and percutaneous transhepatic cholangiography revealed a filling defect in the common bile duct (CBD). The tumor was found to have arisen from the cystic duct and demonstrated papillary growth into the CBD intraluminally through the orifice of the cystic duct. Microscopically, the tumor was identified as papillary adenocarcinoma with invasion limited to the subserosal layer of the cystic duct. There were no signs of nodal metastasis.