[Immunotherapy in metastatic cancer of the kidney]

Evidence accumulated over the last 15 years has clearly demonstrated that metastatic renal cell cancer is an excellent model of the effect of immunotherapy for the treatment of cancer. To date, at least 2 cytokines, interleukin-2 and alpha-interferon have been found to be effective. Objective response is obtained in 15 to 30% of the patients treated with interleukin-2 and 10 to 30% with interferon. Complete response can be achieved in 5% of the cases. Clinically, the best results are seen in patients in good general health and lung metastasis. Complete response for more than 5 years is often observed. Combination protocols with both cytokines and other combinations with infusion of activated lymphocytes have not shown to be more effective than one cytokine alone. It may be possible to obtain higher response rates by combining cytokines with chemotherapy protocols. Surgery still has a role to play however, particularly in patients with an isolate accessible metastasis. Among the perspectives for new immunotherapies, interleukin-12, a strong stimulator of the natural killer population is in phase II trials. Other possibilities include the use of selective populations of lymphocytes as adoptive immunotherapy or combinations using immunotherapy and surgery. Despite the enthusiasm generated by these new techniques, it is imperative to continue rigorous clinical trials in order to develop immunotherapy as a reliable routine treatment.