Biliary hamartomatosis: the diagnostic challenge behind an incidental finding.

Abstract Multiple biliary hamartomas, or Von Meyenburg complexes, are uncommon benign malformations of the intrahepatic bile ducts, typically asymptomatic and identified incidentally. Their principal diagnostic challenge is differentiation from small multifocal hepatic metastases. We report the case of a 62-year-old woman presenting with cholestatic-pattern elevation of liver enzymes, pruritus, and chronic liver disease with significant fibrosis. Cross-sectional imaging demonstrated several subcentimeter hepatic lesions with arterial-phase hyperenhancement, accompanied by persistently elevated CA 19-9 levels. Histological examination of a liver biopsy established the diagnosis of multiple biliary hamartomatosis. Although CA 19-9 may be chronically elevated in the absence of malignancy, isolated cases of progression to intrahepatic cholangiocarcinoma have been documented in patients with underlying chronic liver disease, thereby supporting individualized surveillance strategies. Overall, biliary hamartomatosis is associated with a favorable clinical course.