Renal cell carcinoma accounts for 2-3% of all malignancies. The most common subtype [85%] is the clear cell variant. A total of 30% of patients present with metastatic disease at diagnosis and another 30-40% will develop metastases during the course of the disease. Conventional cancer treatment is not effective, but cytokines including recombinant interleukin-2 (aldesleukin) have demonstrated clinical activity of various degrees. This drug profile provides a review of the literature on studies using aldesleukin in patients with metastatic renal cell carcinoma. Aldesleukin has been used in different dose schedules applying various administration routes, as either monotherapy or in combination with other cytokines, chemotherapy, endocrine treatment and adoptive cellular immunotherapy. Although a large number of randomized trials have been performed with different treatment strategies, it still remains uncertain whether the dose or combination of aldesleukin with other agents substantially influence treatment outcome. It appears that factors other than those that are treatment related are responsible for the course of the disease.