Wünderlich syndrome from a malignant epithelioid angiomyolipoma

Abstract

Angiomyolipoma of the kidney has classically been considered as a tumor of the connective tissue composed of fat, vascular tissue, and smooth muscle. In most cases, it is a tumor with benign behavior that may appear sporadically or associated with tuberous sclerosis syndrome. Macroscopically, these tumors are greyish yellow in color, and under an optical microscope, they are characterised by presenting the three components described. In recent years, several authors have published cases of epithelioid angiomyolipomas characterized by a minimal presence of fat in the tumor, positive for the melanoma-specific antigen, HMB- 45,(1) and on occasion, positive for desmin, melan-A, and others.(2,3) Computed axial tomography and nuclear magnetic resonance studies hardly differentiate epithelioid angiomyolipomas from renal cell carcinoma.(3) We present a case of malignant epithelioid angiomyolipoma in a woman with no tuberous sclerosis, the debut of which was spontaneous retroperitoneal hemorrhage causing hypovolemic shock that required left radical nephrectomy.