Phase II trial of sequential radiation and interleukin 2 in the treatment of patients with metastatic renal cell carcinoma.

Abstract

We have previously demonstrated that local tumor irradiation effectively enhanced the therapeutic effect of interleukin 2 (IL-2) therapy in an experimental murine renal adenocarcinoma model. Based on these preclinical studies, we have designed and initiated a Phase II trial of irradiation combined with IL-2 for the treatment of metastatic renal cell carcinoma. Patients received 800 cGy to the primary or metastatic lesions on days 1 and 15 followed by IL-2 (600,000 IU/kg i.v.) every 8 h on days 4-8 and 18-22. Sixteen patients were entered; all completed treatment and are therefore evaluable for toxicity and response. Two partial remissions were seen for a response rate of 12.5% (95% confidence interval, 0-28.7). There was no increase in toxicity over that which is anticipated from IL-2 alone. The antitumor activity seen in this trial is consistent with what would be expected from high-dose IL-2 alone.