Right-sided pedunculated hepatocellular carcinoma: a form of adrenal metastasis

Pedunculated hepatocellular carcinoma (HCC) or extrahepatic growth of HC C is an uncommon but not rare pathological form, but its genesis is unknown. Right-sided adrenal metastases of HCC that were abutting on or about to fuse with the right hepatic lobe were resected in three patients. The masses seemed to have originated in the para-adrenal tissue, leaving the adrenal gland intact. They were partially supplied by the hepatic artery as well as by the suprarenal artery. Four cases of autopsied pedunculated HCC of the right lobe were also studied. The mass was protruding caudad from the noncancerous parenchyma of the right lobe. Postmortem angiography carried out on one liver showed that only a small portion of the mass toward the liver was supplied from the hepatic artery. These observations suggest that some, perhaps most, of the right-sided pedunculated HCCs represent fusion of the right lobe and para-adrenal or adrenal metastatic HCC. This phenomenon may be explained by possible transport of cancer cells toward the right adrenal gland through the so-called adrenohepatic fusion, a relatively common anatomical change in advanced age.

Case report: right-sided periadrenal metastasis supplied by the hepatic artery. Clue to the genesis of pedunculated hepatocellular carcinoma

The adrenal is the second most common site of haematogenous metastasis of hepatocellular carcinoma (HCC). The right adrenal is much more frequently affected than the left, but no reason has been offered for this difference. An aetiological connection has never been suggested between adrenal metastasis and pedunculated HCC. Hepatocellular carcinoma was resected in two patients who subsequently developed right-sided adrenal metastasis diagnosed by imaging. The adrenal mass was enhanced by hepatic arteriography and took up lipiodol injected into the hepatic artery. Reoperation was performed to remove the adrenal mass, which was abutting on the liver but was readily separable. Histopathologically, the adrenal gland was compressed by a metastatic HCC that developed in the immediate periadrenal tissue or adrenal capsule. By conventional imaging, the adrenal gland could not be recognized and the mass was thought to have arisen within the adrenal gland. In conclusion, periadrenal growth of HCC is a hitherto unrecognized type of metastasis and must have been mistaken either for an adrenal metastasis or a pedunculated HCC in the past. If left unresected, it would have fused with the liver and grown into a pedunculated HCC. Cancer cell invasion through an adrenohepatic fusion is the most likely mode of periadrenal metastasis; it explains the arterial communication between the mass and the liver.

Establishing a diagnosis of adrenal metastasis from hepatocellular carcinoma by 99mTc-PMT hepatobiliary scintigraphy

A 69-year-old woman was diagnosed as having hepatocellular carcinoma (HCC) with liver cirrhosis in October, 1984 and treated by transcatheter arterial embolization (TAE). In June, 1990 she was found to have a huge mass in the left hypochondrium which ultrasonography and computed tomography (CT) scan revealed to be a lett adrenal mass. A 99mTc pyridoxyl-5-methyl tryptophan (99mTC-PMT) hepatobiliary scintigraphy was positive and confirmed metastatic HCC. Although the adrenal mass was large, the HCC itself was controlled well with TAE. The adrenal mass was removed surgically in July, 1990 and the histological findings were compatible with HCC metastasized to the adrenal gland.