adrenohepatic fusion is a relatively common condition that has been reported in the literature and explained as a result of normal aging . however , the presence of a neoplastic process in the adrenohepatic fusion is relatively uncommon , especially when it is a malignant neoplasm . here , we present a patient with a malignant mass consisting of an adrenocortical carcinoma and hepatocellular carcinoma arising from an adrenohepatic union . a 48-year - old male presented with his ruq abdominal pain that is relieved by lying on the right side and sleeping . the patient had no past history of any disease , nor diagnosed of any chronic illnesses . the computed tomography ( ct ) scan for abdomen was done and showed large retroperitoneal mass of heterogeneous density , with heterogeneous contrast enhancement posterior to the liver ( fig . the mass measured 11  11  12 cm displacing the right kidney , and the right lobe of the liver and ivc anteriorly . there was focal invasion of the liver measuring 3.6  6.4 cm at segment 7 . the patient underwent an us - guided core biopsy of the mass that showed malignant cells consistent with both adrenocortical carcinoma and hepatocellular carcinoma ; however , the former diagnosis was favored based on the clinical picture . the patient went for a right hepatectomy with right adrenalectomy , cholecystectomy and excision of associated lymph nodes . the lesion and the excised structures were sent for histopathology that showed a right liver lobe mass attached to it measuring 17  10  7 cm , and the cut section of the mass showed nodular surface with multiple areas of necrosis . slicing of the liver showed a gray white mass measuring 5  5  3 cm , which is adherent to the mass and the remaining liver parenchyma appear unremarkable . the microscopic examination of the mass revealed a moderately differentiated hcc measuring 5 cm in diameter , confined to the liver , < 5 cm from resection margins and no lymph - vascular invasion ( fig . 2 ) , and a separate adrenocortical neoplasm measuring 17 cm in diameter , multiple foci of necrosis , no capsular or lymph - vascular invasion and resection margins were not involved by the tumor ( fig . 3 ) . excised lymph nodes included a single right portal vein lymph node , a gallbladder lymph node and seven para aortic lymph nodes . figure 1:sections of the ct showing a large retroperitoneal mass , focal absence of fat gland and an invasion into the liver.figure 2:section from the hepatic mass showing positive staining of the tumor cells with the hepar ihc stain confirming the hepatic nature of the liver mass.figure 3:section from the adrenocortical mass showing strong positive cytoplasmic staining with low molecular weight cytokeratin - cam 5.2 ihc stain . sections of the ct showing a large retroperitoneal mass , focal absence of fat gland and an invasion into the liver . section from the hepatic mass showing positive staining of the tumor cells with the hepar ihc stain confirming the hepatic nature of the liver mass . section from the adrenocortical mass showing strong positive cytoplasmic staining with low molecular weight cytokeratin - cam 5.2 ihc stain . adrenohepatic fusion is a relatively common observation during autopsies ; however , neoplasms arising from the union are very poorly reported . in our case , an adrenohepatic fusion was detected using a ct scan of the abdomen that showed focal areas of loss of fat gland between the retroperitoneal mass and the liver . dolan defined adrenohepatic union as the adhesion of the liver and the right adrenal cortex with the partial or complete absence of a fibrous capsule dividing the two organs . adrenocortical adenoma arising from an adrenohepatic union was reported in several cases ; however , we could not find a report that describes an adrenocortical carcinoma combined with a hcc from an adrenohepatic union in the literature as the case we present here . a differential diagnosis of hcc must be considered in such a case as the histopathology of the resected lesion shows mixed malignancies of adrenocortical carcinoma in the adrenal part of the lesion and a hcc in the hepatic part and several cases were reported in the literature of a primary hcc extending into the right adrenal directly , or to both adrenals as the first presentation of hcc metastasis , other reports mentioned cases where an hcc has developed in an ectopic liver tissue . on the other hand , an adrenocortical tumor that developed from an adrenal rest inside the liver with radiological findings of hcc okuda introduced a few cases of hcc presenting as pedunculated masses outside the liver most of which had dual blood supply of a hepatic and a suprarenal artery that might support the fusion phenomenon , furthermore , none of the masses were discovered in the left adrenal , which , again , supports fusion and invasion rather than hematogenous spread . core biopsy was reported in different similar cases to be of diagnostic value that changed the presumed diagnosis based solely on imaging modalities . in our case , after using a ct scan to diagnose the patient , a trucut biopsy was done to confirm the diagnosis of an adrenocortical carcinoma invading the liver ; however , an incidental histopathologic finding of co - occurrence of a hcc in the same lesion raised our suspicions , so we went to do a positron emission tomography scan cap to look for any focus of metastasis , which revealed negative results . the patient was followed up for 2 years after the operation without evidence of metastasis or recurrence .