Extrahepatic bile duct hepatocellular carcinoma due to recurrence of hematogenous metastasis 50 months after hepatectomy

BACKGROUND Recurrent hepatocellular carcinoma (HCC) in the extrahepatic bile duct is rare with most cases diagnosed after manifesting sudden obstructive jaundice. Here, we report an extremely rare case of recurrent HCC in the common bile duct due to hematogenous metastasis. CASE PRESENTATION A 66-year-old man underwent an extended left hepatectomy for HCC in the medial segment of the liver. Fifty months later, he presented with sudden obstructive jaundice. Endoscopic retrograde cholangiography showed a space-occupying lesion in the common bile duct, which was suspected as cholangiocarcinoma. Therefore, he underwent extrahepatic bile duct resection and choledochojejunostomy with lymph node dissection. Macroscopically, a polypoid tumor and several nodular tumors were found in the common bile duct, which was obstructed by a tumor thrombus. Histopathologically, the tumors were diagnosed as metastases from the HCC resected 50 months before. Several distinct, nodular tumors were observed in the subepithelium of the common bile duct and had invaded some blood vessels. These findings support the conclusion that the HCC metastasized hematogenously to the extrahepatic bile duct. CONCLUSIONS Recurrent HCC in the extrahepatic bile duct due to hematogenous metastasis is rare, and it is difficult to diagnose. Further similar cases should be accumulated for clarifying the pathological mechanism.