Extensively spreading intraepithelial bile duct carcinoma causing multiple bile duct strictures: report of three cases.

Extensive intraepithelial spread of bile duct carcinoma is a common feature, seen in approximately 18% of all cases. However, this spread is rarely accompanied by bile duct strictures. We herein describe three cases of bile duct carcinoma with multiple bile duct strictures due to extensive intraepithelial spread. In all three cases, the spread of intraepithelial cancer extended into the epithelium of the peribiliary glands along the intrahepatic bile ducts with marked fibrosis on histopathological examination. It is speculated that peribiliary gland involvement by superficially spreading bile duct cancer and subsequent obstructive glandular inflammation with fibrosis might cause intrahepatic bile duct strictures even without interstitial cancer invasion.