Adrenal Cortical Adenoma Developed in Adrenohepatic Fusion, a Mimicry of Hepatocellular Carcinoma - A Case Report

Adrenohepatic fusion is the union of the liver and adrenal gland with close intermingling of their respective parenchymal cells. Adrenal cortical adenoma arising in adrenohepatic fusion tissue is extremely rare, although adrenohepatic fusion itself is relatively common. Here we report a case of a 59-year-old man with a mass in the right lobe of his liver. The mass showed slight hyperattenuation during arterial phase and hypoattenuation during portal phase on dynamic computed tomography with contrast enhancement. On pathology, the mass consisted of round to polygonal cells with clear microvesicular or eosinophilic cytoplasm, arranged in nests or in a trabecular pattern. The tumor cells were positive for inhibin and melan-A, but negative for Hep Par-1. In the periphery of the mass, adrenohepatic fusion was identified between the liver and adrenal gland, and was simultaneously resected with the mass. We report this rare case, and discuss its clinical implications, especially the differential diagnosis with hepatocellular carcinoma.