A case of primary intrahepatic sclerosing cholangitis (PISC) complicated with atypical biliary epithelial proliferation.

A 70-yr-old woman was admitted to our hospital with duodenal ulcer and anemia. The result of liver function test was abnormal and showed persistent elevated alkaline phosphatase levels. Thus, after recovery from duodenal ulcer, endoscopic retrograde cholangiopancreatography (ERCP) was performed; the characteristic "beaded" appearance with band-like strictures and saccular outpouchings affecting the intrahepatic biliary system were found. The diagnosis of primary intrahepatic sclerosing cholangitis (PISC) was made on the basis of the generally accepted diagnostic criteria of primary sclerosing cholangitis (PSC). However, the histological finding from a liver biopsy specimen revealed highly atypical epithelial proliferation of bile ducts. This case of PISC complicated with atypical biliary glandular changes is described, and the distinction between PISC and carcinoma of the bile duct is discussed.