Metastatic renal cell carcinoma arising in a native kidney of a renal transplant recipient.

We report a case of metastatic renal cell carcinoma arising in the native kidney of a renal transplant recipient. A 39-year-old man, who had undergone living renal transplantation from his mother at age 32, presented with complaints of paraplegia of the leg caused by a pathological fracture of the 3rd lumbar vertebra. The bone tumor was extirpated and pathological examination revealed metastatic adenocarcinoma. Abdominal computerized tomography showed a tumor in the right native kidney. Right nephrectomy and resection of the right 7th rib tumor were performed. Pathological evaluation demonstrated renal cell carcinoma of the right native kidney (pT2bpN0pV0M1, mixed cell type, grade 2). Postoperatively, cyclosporine was discontinued and natural interferon-alpha was given. The remaining bone metastasis had completely resolved with no significant sign of rejection 1 year after surgery.