[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. The pathological diagnosis was angiomyolipoma with no malignancy. To our knowledge, renal angiomyolipoma with tumor thrombus has been reported in 62 cases, and pulmonary embolism developed in 9 of these cases. We conclude that surgical treatment is effective in treating angiomyolipoma with tumor thrombus.