Interferon therapy for metastatic renal cell carcinoma.

We have used multiple interferon protocols to treat 274 patients who had metastatic renal cell carcinoma. Leukocyte (alpha) interferon in 50 patients produced 3 complete responses (CR) and 10 partial responses (PR), a 26% response rate that was nearly matched among the next 89 patients treated with recombinant alpha interferon (2 CR, 17 PR, 21%). Other types and combinations of interferon, even when coupled with cytotoxic chemotherapy or other biologic agents, did not produce better results. Interferon has definite activity against renal cell carcinoma, but clinical experience has not yet defined the optimal type, dose, and treatment schedule.