Early neoplasias of the gallbladder and bile duct: an "unstable" biliary epithelium?

Benign tumours of the biliary tree are rare. In particular, only anecdotal cases of intraductal villous adenomas have been reported. The polyp-cancer sequence has not been observed in the biliary epithelium, in contrast to the paradigm of colorectal carcinogenesis. This report presents the case of a 64-year-old woman with a past history of cholelithiasis who had two early neoplasias involving the biliary epithelium: an adenocarcinoma in situ of the gallbladder and a common bile duct (CBD) villous adenoma with high-grade dysplasia. The tumours presented 4 years apart. The clinical features and combined radiological, cytological, and surgical modalities leading to the diagnosis of intraductal villous adenoma are presented. The endoscopic ultrasound (EUS) characteristics of villous adenoma of the CBD are described. While the prognosis on both occasions appears excellent following curative resections of both tumours detected at an early stage, it is possible that further neoplasia involving the biliary tree may recur. There are currently no data on optimal surveillance modalities. It may be hypothesized that the gallbladder and biliary epithelium share a similar mechanism for carcinogenesis to that observed in the colonic adenomacarcinoma sequence.