Mass-forming inflammatory periductal fibrosis mimicking hilar bile duct carcinoma.

A case of a rare benign biliary lesion at the hepatic hilum mimicking hilar bile duct carcinoma is reported. A 73-year-old man was found to have gastric cancer by gastrointestinal fiberscopy. Dilated right intrahepatic bile ducts and a 2-cm mass in the right hepatic duct were demonstrated by further imaging investigations. He was finally diagnosed as having hilar bile duct and gastric carcinomas, and underwent right portal vein embolization followed by a single-stage extended right hepatectomy and total gastrectomy. Pathologically, however, the lesion in the right hepatic duct showed inflammatory changes with periductal fibrosis, without any signs of malignancy. A literature search revealed 11 such cases including the present one.