Angiomyolipoma of the renal sinus: diagnosis by percutaneous biopsy

We report a case of angiomyolipoma of the renal sinus discovered incidentally during an evaluation for microscopic hematuria. Diagnosis was confirmed by percutaneous aspiration biopsy performed with magnetic resonance imaging control allowing differentiation of this entity from other fatty tumors of the renal sinus including liposarcoma, lipoma, and sinus lipomatosis.