A CASE OF RENAL ANGIOMYOLIPOMA

Renal angiomyolipoma is a relatively rare mesodermal mixed tumor. In Japan, 124 cases have been reported. This paper describes our recent experience with a case of renal angiomyolipoma without accompanying nodular sclerosis. The patient was a 48-year-old woman who was admitted under the condition of acute heart failure and was unexpectedly found by abdominal echography to have a mass at the upper pole of the left kidney. Because detailed examination suggested a malignant tumor in the left kidney, the kidney was excised. Histopathological examination of the excised specimen showed a mixture of abundant fatty, muscular and vascular tissues, leading to a diagnosis of renal angiomyolipoma. Preoperative diagnosis of this condition is relatively easy in patients with a complication of nodular sclerosis, who show the triad of epilepsy, mental disturbance and facial sebaceous adenoma. In contrast, cases without that complication are difficult to differentiate from renal carcinoma. The number of cases diagnosed preoperatively has increased recently with the use of CT, because the CT value of the fatty tissue in this tumor is low.