Interleukin 2 is active in metastatic renal adenocarcinoma which is usually considered as a chemoresistant tumour; 20 to 30% objective responses, including 5 to 10% complete remissions, are reported using various treatment schedules. Toxicity, though of great concern, is now controlled and IL2 is mostly used in standard oncology units or as an out-patient subcutaneous treatment. Even if IL2 is now a registered drug in France, many questions remain however, regarding the optimal schedule and dose, the interest of combining IL2 with interferon alpha or the predictive factors of response of this therapy.