ABSTRACT
Renal angiomyolipomas are benign mixed mesenchymal tumors, which are composed of atypical blood vessel, smooth muscle and fat cells. A 34-year-old woman presented with a palpable right abdominal mass, accompanied with discomfort. A CT scan showed a large right perinephric mass, with heterogeneous density, surrounding the kidney, with enlargement of the regional lymph nodes. The presumptive diagnosis was one of a malignant tumor of the retroperitoneum, with lymph node metastasis or an angiomyolipoma, involving both the kidney and lymph nodes. A right radical nephrectomy, including the tumor, was performed. The final diagnosis was an angiomyolipoma arising from the kidney, with the dissected lymph nodes having the same pathology. There was no evidence of a tumor recurrence during the six month follow-up period. This was an unusual case of a multicentric angiomyolipoma.