A case of extrahepatic bile duct metastasis of parotid gland cancer

A 62-year-old man was referred to our hospital with the upper abdominal pain and the elevation of the biliary duct enzymes. The patient has the history of removal of the left parotid gland, which was diagnosed with salivary duct carcinoma ten years ago. Computed Tomography and IDUS showed entire obstruction of the middle bile duct, caused by an extraductal mass and its infiltration. Biliary biopsy was performed, and the histological findings revealed adenocarcinoma cells which were positive for HER2 and AR. We placed a full-covered metallic stent in the common bile duct and confirmed decline of the biliary duct enzymes. This is a rare case of parotid gland cancer metastasis to the common bile duct. An accurate diagnosis may be possible by considering the possibility of metastatic parotid gland cancer and comprehensive evaluation of the medical history and the histological features.