Between October 1987 and June 1992, 244 patients with metastatic renal carcinoma were referred to our Institute. One hundred and sixty-nine were included in immunotherapy protocols. The 40 most recent patients were included in the ongoing multicentric randomised Crecy study. The previous patients were treated with IL2 as a continuous infusion or high doses intravenous IL2 combined with alpha interferon (IFN) or a combination of IL2 and IFN as subcutaneous low doses. Some patients received as rescue treatment a combination of IL2 with Tumor Necrosis Factor (TNF). First line immunotherapy with cytokines gave 14-25% response rates in these patients with 5-10% of complete persistent remissions. The most intensive regimen was responsible for the most severe toxicity as well as the highest response rate. TNF does not appear to be of great concern since its systemic administration induced important limiting toxicities. This work emphasizes the need for prospective studies in order to evaluate the optimal mode and schedule of treatment as well as to investigate the impact of immunotherapy on survival.