Metastasis and invasion of hepatocellular carcinoma mimicking a right adrenal tumor.

A 60-year-old man presented with a large right adrenal mass. Adrenal primary carcinoma invading the liver and retrohepatic inferior vena cava was suspected after preoperative imagings, which included ultrasonography, computed tomography, selective hepatic and adrenal angiography, and magnetic resonance imaging. An en bloc resection of the right kidney, right adrenal gland, posterior hepatic segment, and laterodorsal of the vena cava was performed using an active veno-venous bypass. The defect of the inferior vena cava was closed using a 6 x 10 cm patch of horse pericardium. The cut surface of the resected specimens revealed a smaller necrotic intrahepatic tumor as well as a large extrahepatic tumor which involved the right adrenal gland and extended continuously to the liver, mimicking an adrenal tumor. As the histological features of the two tumors disclosed the same moderately differentiated hepatocellular carcinoma with a trabecular or pseudoglandular pattern, a huge mass of the right adrenal gland with invasion into the right lobe of the liver, which mimicked a primary adrenal tumor, was diagnosed as metastatic hepatocellular carcinoma from a primary hepatic tumor.