Peribiliary Cysts Mimicking Primary Sclerosing Cholangitis and Cholangiocarcinoma.

Peribiliary cysts are cystic dilatations resulting from obstruction of extramural peribiliary glands. They are usually benign, may arise from the intrahepatic and extrahepatic bile ducts, and do not communicate with the biliary tree. They may, however, be confused with alternative diagnoses, resulting in unnecessary investigations with profound clinical implications. We present a case of a 42-year-old male, in whom this entity was misdiagnosed as primary sclerosing cholangitis with cholangiocarcinoma.