Regression of multiple osseous metastatic renal cell carcinoma.

A 65-year-old man with 6 osseous metastatic lesions was successfully treated by nephrectomy. Five of 6 metastatic tumors, 2 of which were histologically proved, dramatically regressed and disappeared roentgenographically. The other metastasis was removed by amputation 4 years prior to the nephrectomy. No apparent complication was found after the nephrectomy and the patient is in very good health. The factors responsible for regression of osseous metastatic renal cell carcinoma cannot be fully explained. The only common treatment given to 4 patients whose osseous renal cell cancer regressed, was nephrectomy. Since every therapy for metastatic renal cell cancer is unreliable, palliative nephrectomy seems to be justified as a treatment of choice even when osseous metastases are noted and there is a possibility of regression of metastatic lesions. Regression of osseous metastasis from renal cell carcinoma is extremely rare and only 3 cases have been reported.