Immunotherapy, also called biologic therapy, is designed to boost the body’s natural defenses to fight cancer. It uses materials made either by the body or in a laboratory to improve, target, or restore immune system function.
Interleukin-2 (IL-2) is a drug that has been used to treat later-stage kidney cancer. It is a cellular hormone called a cytokine that is produced by white blood cells and is important in immune system function, including the destruction of tumor cells.
High-dose IL-2 can cause severe side effects, such as low blood pressure, excess fluid in the lungs, kidney damage, heart attack, bleeding, chills, and fever, so patients may need to stay in the hospital for up to 10 days during treatment. However, some symptoms may be reversible. Only centers with expertise in high-dose IL-2 for kidney cancer should recommend IL-2. Some centers use low-dose IL-2 because it has fewer side effects, although it is not as effective.
Alpha-interferon is another type of immunotherapy used to treat kidney cancer that has spread. Interferon appears to change the proteins on the surface of cancer cells and slow their growth. Although it has not proven to be as beneficial as IL-2, alpha-interferon has been shown to increase survival when compared with an older treatment called megestrol acetate.
Researchers have tested many combinations of IL-2 and alpha-interferon for patients with advanced kidney cancer, and these treatments have also been combined with chemotherapy. It has not been shown in research studies that these combinations are better than IL-2 or interferon alone.
Researchers are working to learn more about how IL-2 and interferon destroy kidney cancer cells and which patients can benefit the most from these treatments. Newer forms of immunotherapy called checkpoint inhibitors are also being tested in clinical trials .