Intrahepatic adrenocortical adenoma arising from adrenohepatic fusion mimicking hepatic malignancy: Two case reports

RATIONALE: Intrahepatic adrenocortical adenoma (IAA) arising from adrenohepatic fusion (AHF) is rare and its imaging findings are not well established. Moreover, it is easily misdiagnosed as malignant hepatic tumor in patients at risk of malignancy. Its key finding is the connection between the tumor and adrenal gland. When IAA from AHF is suspected, biopsy should be considered to avoid unnecessary surgery. Herein, we report 2 cases of IAA from AHF. PATIENT CONCERNS: A 59-year-old woman was admitted due to a 1.5-cm hypoechoic nodule in the right hepatic lobe detected on ultrasound for hepatocellular carcinoma (HCC) surveillance due to chronic hepatitis B. Contrast-enhanced computed tomography (CT) and gadoxetic acid-enhanced magnetic resonance imaging (MRI) were performed to evaluate the hepatic mass. Another 75-year-old woman was admitted due to rectal adenocarcinoma detected on colonoscopy. Contrast-enhanced CT depicted a 2.5-cm mass in the right hepatic lobe. DIAGNOSIS: In case 1, CT and MRI showed a 1.5-cm subcapsular mass in the right hepatic lobe with typical findings of HCC in a patient with chronic hepatitis B. The mass was confirmed as IAA from AHF after the laparoscopic surgery. In case 2, CT showed advanced rectal malignancy and a 2.5-cm poorly enhancing mass in the right hepatic lobe. The tentative diagnosis was hepatic metastasis. However, based on the connection between the tumor and adrenal gland during preoperative review, the presumed diagnosis was changed to IAA from AHF, which was confirmed on biopsy. INTERVENTIONS: The hepatic mass connected with the right adrenal gland was laparoscopically resected in case 1. Laparoscopic lower anterior resection for rectal malignancy and percutaneous biopsy for the hepatic mass were performed in case 2. OUTCOMES: The first patient had an uneventful recovery, without recurrence on the 3-year follow-up CT. The second patient had an uneventful postoperative course and has been alive for 12 months postoperatively without pathologically proven IAA changes on follow-up CT. LESSONS: When hepatic mass is found adjacent to the right adrenal gland on imaging, the connection between the tumor and adrenal gland should be investigated. When IAA arising from AHF is suspected, biopsy should be considered to avoid unnecessary surgery.