Crossed renal ectopia is one of the rarest urinary system anomalies. It is more often seen at autopsy than in clinical practice. Most cases of renal ectopia remain asymptomatic during life and are diagnosed incidentally. Renal ultrasonography, intravenous pyelography, computerized tomography, and renal scintigraphy (technetium-based tests) are the imaging methods used for diagnosis. Demonstration of crossed renal ectopia is important because it is a predisposing factor for obstruction, infection, and neoplasia of the urinary system. We report two male patients who had unremarkable clinical findings. Both had left-to-right inferior crossed renal ectopia with fusion. Additionally, the first patient had a history of surgery for a recurrent inguinal hernia, whereas the second had crossed fused renal ectopia associated with nephroptosis. Surgeons should be aware of ectopic and fused kidneys to minimize perioperative complications because of the uncertain anatomy.

Renal angiomyolipoma is a benign kidney tumor, which is characterized by the presence of mature or immature fat tissue, thick-walled blood vessels, and smooth muscles. However, there is a rare possibility of transformation to a malignancy. This transformation could be toward sarcoma. And also angiomyolipoma could be associated with renal adenocarcinoma in the same kidney. The aim of this study is to show the association of angiomyolipoma with complex clinical situations such as malign transformation, simultaneous occurrence with adenocarcinoma, bilateral tumors with tuberous sclerosis or Wunderlich Syndrome. Findings of clinical presentation, pathological evaluation, urography, ultrasonography, and computerized tomography of 19 patients who were diagnosed angiomyolipoma in our clinic during 1994-2003 were examined retrospectively. Our records indicated that radical nephrectomy was performed in three cases of angiomyolipoma in which the differential diagnosis from adenocarcinoma could not be made and in another case of angiomyolipoma, which was associated with adenocarcinoma. Simple nephrectomy was performed in four symptomatic angiomyolipoma cases with tumor size larger than 4 cm and partial nephrectomy in another case. In one case, renal angiomyolipoma was associated with adenocarcinoma in the same kidney. In one case, post-operative recurrence of angiomyolipoma developed 7 months after nephrectomy. This patient was diagnosed low-grade leiomyosarcoma. Angiomyolipoma is regarded as a benign tumor of the kidney; however, it may also show aggressive behaviors and rarely transform to sarcoma. It may also exist in the same kidney along with adenocarcinoma or sarcoma.