Interleukin-2 is the standard treatment for patients with metastatic renal cell cancer. However, after more than a decade of clinical trials designed to find the optimal dose and schedule of interleukin-2, the ideal treatment regimen has yet to be determined. It is also not clear what alfa interferon adds to the treatment of metastatic renal cell cancer.
Several studies of interleukin-2 conducted by the Cytokine Working Group were reviewed by physicians participating in these clinical trials. These clinical trials were carried out in attempts to improve on the results of high-dose interleukin-2 in patients with metastatic renal cell cancer. The following regimens were evaluated: high-dose interleukin-2 alone, high-dose interleukin-2 plus alfa interferon, moderate-dose subcutaneous interleukin-2 plus alfa interferon and moderate-dose interleukin-2, alfa interferon and 5-fluorouracil. The overall response rates were similar (11-17%). However, the high-dose interleukin-2 regimen produced a 7% complete response rate compared to 0-4% for the other regimens. The average duration of response was 53 months for the high-dose interleukin-2 regimen and 7-12 months for the other regimens.
A current ongoing clinical trial is comparing the best high-dose regimen to the best outpatient regimen of interleukin-2 and alfa interferon to confirm these findings. In the absence of a clinical trial, high-dose interleukin-2 appears to be the treatment of choice for renal cell cancer. (
Cancer Journal of the Scientific American, Vol 3, Suppl l, pp S73-78, 1997)