[Management of isolated angiomyolipoma of the kidney]

Four patients presented isolated angiomyolipomas of kidney in the absence of any form of phakomatosis such as Bourneville's disease. The tumor was removed by partial nephrectomy in only one case, after histology of a fresh specimen confirming the presence of an angiomyolipoma without signs of cancer. In another patient it was impossible to perform conservative surgery because of dissemination of the angiomyolipoma throughout the kidney. Symptomatology suggestive of the disorder includes lumbar pain, kidney tumor and more rarely hematuria. Diagnosis is difficult despite availability of ultrasound and CT scan imaging, which has supplanted renal arteriography. Confirmation requires histology of a fresh specimen. Operative treatment is essential to avoid the risk of intra- and peri-tumoral hemorrhage, particularly during pregnancy. Partial nephrectomy or excision of tumor is possible when the diagnosis has been established, if excision involves healthy parenchyma and if after strict hemostasis at least one third of renal parenchyma remains.