Abstract
Background: Granular cell tumors are rare tumors most often located in the oral cavity, skin or subcutaneous tissue. The occurrence of this tumor in the biliary tree is extremely rare. Methods: Two patients are described presenting with biliary obstruction due to a tumor at the hepatic duct confluence. One patient is a 38-year-old white male with concomitant cutaneous granular cell tumors, and the other a 50-year-old white female. Results: Hilar excision was performed in both patients. Histopathology of the tumors revealed a proliferation of cells with granular cytoplasm, diagnosed as granular cell tumor. Conclusion: At preoperative examination, hilar granular cell tumors are difficult to differentiate from cholangiocarcinoma, sclerosing cholangitis or more common benign biliary tumors. Treatment consists of surgical excision after which prognosis is favorable.