Adenosquamous carcinoma of the gallbladder with tumor thrombus in left portal trunk

We report a surgically resected case of adenosquamous carcinoma of the gallbladder accompanied by portal tumor thrombosis, which is regarded as a rare complication. A 73‐year‐old man was admitted to our hospital because of epigastralgia. Preoperative examinations led to a diagnosis of advanced gallbladder carcinoma with liver metastasis, and operation was performed. Since intraoperative ultrasonography showed a tumor thrombus in the left main portal trunk originating from the metastatic lesion in the left medial segment of the liver, extended left lobectomy with extrahepatic bile duct resection and lymph node dissection was performed, instead of right trisegmentectomy, as proposed preoperatively. Histological examination revealed adenosquamous carcinoma of the gallbladder with medullary growth that was similar to the hepatocellular carcinoma, most notably in the metastatic lesion of the liver and in the portal tumor thrombus. We discuss the relation between portal tumor thrombosis and medullary tumors, and note the atypical operative method employed.