[A resected case of mucin-secreting malignant papillomatosis (villous tumor) of ductus choledocus and left intrahepatic duct].

A resected case of remarkably mucin-secreting malignant papillomatosis (villous tumor) of the ductus choledocus and left intrahepatic duct in a 79 year-old female was reported. In this case, cholecystectomy and choledocho-duodenal anastomosis for the gallbladder stone were performed 14 years ago. Villous or papillary tumors arose in the ductus choledocus and spread into the left intrahepatic duct. Histological examination revealed villous proliferation similar to the villous tumor in the large intestine, in which cancerous and adenomatous changes intermingled showing remarkable mucin secretion. Tumor invasion was limited in the wall without extracanal dissemination, and nodal metastasis was absent. Interestingly, exceeding mucin-secretion was observed as the frog-egg like appearance in the ductus choledocus and as the regurgitation into the stomach by the endoscopic examination. This type carcinomas usually show favorable prognosis compared with the ordinary adenocarcinomas of the bile duct.