Adrenal Rest Tumor of the Liver Preoperatively Diagnosed as Hepatocellular Carcinoma

Hepatic Adrenal Rest Tumors Mimicking Hepatocellular Carcinoma: A Case Report and Review of the Literature

Adrenal rest tumors are rare collections of aberrantly located adrenocortical tissue. They are most commonly found in the kidneys, and hepatic involvement is rare with few published case reports. When located in the liver, imaging findings are frequently indistinguishable from hepatocellular carcinoma (HCC), but when resected, histologic examination shows adrenocortical tissue. Here, we present a patient with a history of nonalcoholic steatohepatitis with advanced fibrosis who was identified as having HCC by cross-sectional imaging but was found to have a hepatic adrenal rest tumor (HART) after resection. HARTs can share imaging characteristics with HCC, and this alternative diagnosis should be considered, especially for hepatic segment VII lesions.

Hepatic adrenal rest tumor in a patient with multifactorial liver cirrhosis: a case report with CT and MRI findings and pathologic correlation

Background

Adrenal rest tumor is an ectopic collection of adrenocortical cells in an extra-adrenal site, more frequently located around the kidney, retroperitoneum, spermatic cord, para-testicular region and broad ligament, but very rarely occurring also in the liver. Hepatic adrenal rest tumor poses a diagnostic challenge in differentiating it from hepatocellular carcinoma, particularly in a cirrhotic liver.

Case presentation

An 83-years-old male was referred to our hospital by his family doctor for hepatological evaluation due to multifactorial liver cirrhosis. Ultrasound revealed a centimetric hypoechoic nodule in the VI hepatic segment in the context of a liver with signs of cirrhosis and steatosis. The patient first underwent MRI and then CT, which showed a fat containing focal liver lesion in the subcapsular location of the right lobe, strictly adjacent to the homolateral adrenal gland. The nodule was hypervascular in the arterial phase, washed out in the portal-venous and transitional phases, resulting hypointense in the hepato-biliary phase at MR imaging. In the suspicion of a hepatocellular carcinoma, the nodule was surgically removed, and the patient’s postoperative course was unremarkable. The final histopathological diagnosis was of adrenal rest tumor of the liver.

Conclusions

Hepatic adrenal rest tumor is an extremely rare hepatic tumor, often without any clinical manifestation, that can also occur in the cirrhotic liver as in our case. Although there are not specific imaging findings, the possible diagnosis of HART should be considered when we observe a well-defined lesion in the subcapsular location of the right lobe, with fat containing, hypervascularity after contrast medium injection and vascular supply from the right hepatic artery.