Fine needle aspiration diagnosis of angiomyolipoma of the liver using a cell block with immunohistochemical study. A case report.

Fine needle aspiration diagnosis of hepatic angiomyolipoma has been reported rarely. Below we report one such case diagnosed by examination of a cell block. The presence of epithelioid smooth muscle cells, mature adipocytes, thick-walled vessels and extramedullary hematopoiesis established the diagnosis. It was further substantiated by positive staining of the epithelioid cells for muscle-specific actin (HHF-35). The epithelioid cells were also immunoreactive with a melanocytic marker, HMB-45, but not with desmin, vimentin, cytokeratin or S-100 protein. HMB-45 might prove to be a sensitive marker for the epithelioid smooth muscle component of the tumor. The advantage of the routine use of a cell block in fine needle aspiration is emphasized.