[Renal Angiomyolipoma Extending into the Renal Vein --A Case Report-].

We report a case of left renal angiomyolipoma extending into the renal vein. A 67-year-old woman showed a left renal tumor which was 6 cm in diameter and had density equal to fat tissue in computed tomography. We suspected liposarcoma and performed radical nephrectomy and resection of thrombus.