Cytokine-based therapy for metastatic renal cell cancer.

The use of recombinant gene technology to produce commercially available amounts of cytokines heralded an era of clinical applications of immunotherapy. Although the response rates to cytokine therapies are modest and sometimes occur at the expense of great cost and toxicity, they are proof of the principal that even large tumor burdens can be overcome by purely immune modulation. The interleukins and the interferons have been used in various phases of clinical trials in RCC. The maturation and final results of phase III trials are needed to guide clinical practice. In the meantime, the knowledge gained clinically and in the laboratory should lead to continued improvements and outcomes in immunotherapy for RCC.