[Systemic immunotherapy of metastatic renal cell carcinoma and long-term outcome]

Within the last 10 years, immunotherapy has progressively become an established treatment for patients with metastatic renal cell carcinoma. The cytokines interleukin-2 (IL-2) and interferon-alpha (IFN-alpha) are the substances that have shown the greatest effects. Both have been approved for the treatment of patients with metastatic renal cell carcinoma in Germany. Subcutaneous application of these frequently combined cytokines is the schedule of immunotherapy used most often in Germany. Combined cytokine therapy (IL-2 and IFN-alpha) achieves response rates comparable to more aggressive immunotherapies. The retrospective analysis of treatment results from 66 patients with a follow-up of at least 5 years after the start of combined s.c. IL-2 and s.c. IFN-alpha +/- 5-fluorouracil (response classification: CR: 7, PR: 11, SD: 20, PD: 28) shows that the classification of the treatment results according to WHO criteria is the strongest predictor for survival compared with basic factors such as TNM status, grading, or number of metastatic sites. The combination of cytokine treatment with other treatment modalities (for example, surgical intervention) leads to a differentiated treatment according to the tumor status of the patient with metastatic renal cell carcinoma. Specific immunotherapies are still experimental. No approval has been granted for any of these treatments. Only standardization of these protocols can lead to a supplemental form of immunotherapy. Although several aspects of cytokine-based immunotherapy need further scientific evaluation, it is the treatment of choice for patients with metastatic renal cell carcinoma. However, for further progress in this field, prospective evaluation of immunotherapy for metastatic renal cell carcinoma is still needed. The German society for immunotherapy serves as a platform for this research.