[A case of renal cell carcinoma developing from a dysplastic kidney]

A case of renal cell carcinoma developing from a unilateral dysplastic kidney is reported. A 33-year-old woman was admitted to our hospital because of lumbago due to metastatic cancer to the bones. She was treated with interferon and combination chemotherapies, but died nine and a half months after initiation of the therapy. Autopsy revealed a widely metastasized renal cell carcinoma originating from a dysplastic left kidney. This is the second such case in the literature. Clinical management of renal dysplasia should take into consideration the possibility of developing malignancy.