[A case of primary biliary malignant lymphoma mimicking Klatskin tumor]

Primary non-Hodgkin's lymphoma of the extrahepatic bile duct presenting as obstructive jaundice is extremely rare. A 60-year-old man was admitted due to suddenly developed jaundice. Computerized tomography and endoscopic retrograde cholangiopancreatography showed a tumor at the proximal common hepatic duct. These clinical and radiologic findings resembled those of Klatskin tumor. The resection of the common hepatic duct tumor, lymph node dissection, and Roux-en-Y hepaticojejunostomy were carried out. There was no regional lymph node metastasis and no residual tumor at the resection margins. Histology and immunohistochemistry of the resected specimen confirmed a diffuse large B-cell malignant lymphoma involving the common hepatic duct. The patient is scheduled to receive adjuvant chemotherapy. In summary, primary non-Hodgkins lymphoma of the extrahepatic bile duct, despite its rarity, should be considered in the differential diagnosis of causes for obstructive jaundice. An accurate histopathologic diagnosis and surgical resection combined with chemotherapy may be the approach to offer a chance for cure.