Primary angiosarcoma arising in an angiomyolipoma of the kidney: case report and literature review

Background Primary angiosarcoma of the kidney is a rare and aggressive malignant tumor presenting with a recognizable vascular differentiation. Its prognosis is fatal and the pathogenesis remains unclear. Renal angiomyolipoma is a relatively infrequent renal cortical neoplasm and is composed of variable proportions of adipose tissue, spindle cells, epithelioid smooth muscle cells and abnormal thick-walled blood vessels.