Intraductal oncocytic papillary neoplasm of the extrahepatic biliary tree: first report.

Tumors with oncocytic differentiation may occur in a variety of organs, but are extremely rare in the biliary system. Intraductal oncocytic papillary neoplasms (IOPNs) were first described in the pancreas to differentiate a rare subset of pancreatic neoplasm from the intraductal papillary mucinous neoplasms (IPMNs). IOPN of the extrahepatic biliary tree has not been previously described. We describe the first case of an intraductal oncocytic papillary neoplasm at the bifurcation of the common hepatic duct in a 52-year-old white male with a two-year history of intermittent biliary obstruction.