Recent developments in renal cell cancer immunotherapy.

Various immunotherapeutic approaches for the treatment of renal cell carcinoma (RCC) have been developed for > 90 years. Existing immunotherapeutic strategies against RCC include: systemic administration of cytokines; therapeutic vaccines based on tumor cells or dendritic cells; monoclonal antibodies; and adoptive immunotherapy (T cell transfer or allogeneic hematopoietic cell transplantation). However, the overall efficacy of immunotherapy for advanced RCC remains moderate. With the advent of molecularly targeted biological therapies that turned out to be significantly effective in the treatment of metastatic RCC, to many oncologists immunotherapy may seem to be moving into the periphery of RCC treatment strategies. However, for the last 2 years there has been significant progress made in immunotherapeutic approaches for the treatment of RCC. Immunotherapy still remains the only systemic therapeutic strategy that is believed to potentially cure RCC patients. The development of active and passive specific immunotherapeutic approaches, along with the possibility to 'switch off' particular immunosuppressive mechanisms (e.g., elimination of regulatory T cells, blockage of cytotoxic T lymphocyte antigen-4 signaling), have paved the way for future trials of new immunotherapies of RCC. However, the new studies will have to enroll optimally selected patients (nephrectomized, with non-massive metastases and good performance status) and will use tumor response criteria that are specifically optimized for clinical trials of immunotherapy.