Congenital bile duct cyst: a premalignant lesion of the biliary tract associated with adenocarcinoma--a case report.

The incidence of carcinoma arising in the wall of a congenital bile duct cyst is high and there is no doubt that these lesions represent a precancerous state of the biliary tract. In almost all cases congenital bile duct cysts are related to anomalous arrangements of the pancreaticobiliary duct system which seems to play a crucial role in the development of cystic bile ducts and biliary carcinogenesis. Bile stasis together with reflux of pancreatic juice causing longstanding inflammation and activation of bile acids might be the factors in carcinogenesis of the exposed bile duct epithelium in the cystic wall. In the case of primary or secondary extrahepatic bile duct cysts, primary excision is mandatory because of the high risk to develop biliary cancer with even nowadays poor prognosis despite advantages in biliary surgery during the last years. We report a case of a young woman in which bile duct cancer was found arising in the wall of a congenital bile duct cyst. Despite radical surgery the outcome was poor proving the high malignant potential of bile duct cancer. The question of possible tumor seeding in hepatobiliary surgery is discussed as a way of inducing hepatobiliary metastatic tumors.