Long-term interferon treatment in metastatic renal cell carcinoma.

20 patients with progressive metastatic renal cell carcinoma entered a trial in which the effect of a long-term 6-month regimen of recombinant interferon alpha-2b (rIFN) was studied. 15 patients were evaluable. 4 remissions were detected: 1 complete, and 3 partial. All remissions were seen within 3 months of the start of treatment. We conclude that a 3-month rIFN treatment in metastatic renal cell carcinoma is sufficient to make a distinction between responders and non-responders. A review of the recent literature supports this conclusion.