Renal angiomyolipoma

An unusual case of a patient with tuberous sclerosis who presented initially with renal symptoms is presented. Electromicroscopic observations showed the smooth muscles to contain myofilaments and an unusual amount of glycogen. Although the response of the tumor vessels to epinephrine in angiomyolipoma is considered similar to that of renal cell carcinoma in that no vasoconstriction occurs, the reverse occurred in our case. A thin, lucent cleavage line around portions of the periphery of the angiomyolipoma was also noticed. Isolated angiomyolipoma in patients without tuberous sclerosis is difficult to differentiate from renal cell carcinoma; therefore, radical nephrectomy is usually the treatment of choice. Angiomyolipomas associated with tuberous sclerosis are easier to diagnose and are multiple and bilateral; therefore, a more conservative approach usually is indicated.