Hepatic angiomyolipoma-misdiagnosis as hepatocellular carcinoma: A report of 14 cases

Angiomyolipoma (AML) is a rare benign mesenchymal tumor of the liver, composed of a varying heterogeneous mixture of three tissue components: blood vessels, smooth muscle, and adipose cells. It has recently been proposed that the perivascular epithelial cell (PEC) is the common progenitor[1，2] Since its first description by Ishak in 1976[3], there have been more than 100 cases reported in the English literature[4-6]. With the advance of radiological techniques, many more tumors are being diagnosed by the means. But radiological findings of AML may only be suggestive of the lesion; its definitive diagnosis requires histological confirmation[9-19]. Some authors regard renal and hepatic AMLs, pulmonary and soft tissue lymphangiomyomatosis[2], pulmonary and pancreatic clear cell “sugar” tumor, and cardiac rhabdomyoma as closely related groups of tumors, based on their morphologic overlap and common immunoreactivity for HMB-45[l]. They show different microscopic appearances, however, according to their organ of origin. The goals of this study were to highlight more subtle morphology and to gain possible insights into the differential diagnosis that could provide important information about this disease.