[Hepatic epithelioid angiomyolipoma: a clinicopathologic analysis of 25 cases].

Objective: To study the clinicopathologic features, immunophenotype, histological diagnosis and prognosis of hepatic epithelioid angiomyolipoma.
Methods: Clinical data of 25 cases of hepatic epithelioid angiomyolipoma were collected along with follow-up study of the patients. The pathological features were documented and immunohistochemical study of various markers was performed with an emphasis on diagnosis and differential diagnosis.
Results: Hepatic epithelioid angiomyolipoma was more commonly found in young women without characteristic clinical symptoms. Its morphological features were characterized by marked cytological atypia, relatively rare mitotic figures; radial distribution of tumor cells around the thin-walled blood vessels or muscular vessels; and the presence of common multinucleated giant cells and large ganglion-like tumor cells. The tumor cells expressed both melanoma cell markers (HMB45, MART-1) and smooth muscle cell markers (SMA). Tumor cells expressed various other markers including ER 16% (4/25), PR 32% (8/25), TFE3 24% (6/25) and p53 60% (15/25).
Conclusions: Hepatic epithelioid angiomyolipoma has variable morphological features and characteristic immunohistochemical phenotype. The differential diagnoses include a variety of tumors. The biological behavior of the tumor tends to be benign.