[The treatment of renal cell carcinoma with recombinant human leukocyte interferon]

Recombinant human leukocyte (alpha) interferon was administered i.m. at the initial dose of 3 X 10(6) U/day to 27 patients with measurable metastatic renal cell carcinoma during the past 2 years. The results of 22 of these patients were evaluable. Three patients (13.6%) showed partial response; 3 patients (13.6%), minor response; 7 patients (31.8%), no change; and 9 patients (40.9%), progressive disease. Major toxicity consisted of fever (55.5%), anorexia (44.4%), malaise (22.2%), elevation of GOT/GPT (48.1%), leukopenia (44.4%) and thrombocytopenia (29.6%). When the 3 patients who showed stabilization (S) and the 2 patients who showed mixed effects (ME) among the 7 patients who showed no change are classified into the responded group, half the patients had some response to interferon. Characteristics of these responders (PR + MR + ME + S) were good performance status, relatively longer disease-free interval, metastases limited to the lungs or metastasis to lungs and one other organ excluding the liver, and frequency of interferon-induced thrombocytopenia. Interferon administration is still being continued to 4 patients on an outpatient basis, 5 patients are hospitalized and 13 patients have died. In conclusion, patients with pulmonary metastases seem to be the best responding group for interferon treatment in renal cell carcinoma and further trials, especially combined regimens with chemotherapy and/or other kinds of interferon should be tested.