The goal of biologic therapy is to boost the body’s immune system to help fight off or destroy cancer cells.
Cytokines are man-made versions of natural proteins that activate the immune system. The cytokines used most often to treat kidney cancer are interleukin-2 (IL-2) and interferon-alpha. Both cytokines can cause kidney cancers to shrink in a small percentage of patients.
In the past, IL-2 was commonly used as first-line therapy for advanced kidney cancer, and it may still be helpful for some people. But because it can be hard to give and can cause serious side effects, many doctors only use it in patients who are healthy enough to withstand the side effects, or for cancers that aren’t responding to targeted drugs.
Although only a small percentage of patients respond to IL-2, it is the only therapy that appears to result in long-lasting responses. Doctors are now looking to see if certain patient and cancer characteristics can help predict if IL-2 will be helpful.
Giving high doses of IL-2 seems to offer the best chance of shrinking the cancer, but this can cause serious side effects, so it is not used in people who are in poor overall health to begin with. Special care is needed to recognize and treat these side effects. Because of this, high-dose IL-2 is only given in the hospital at certain centers that are experienced with giving this type of treatment.
The possible side effects of high-dose IL-2 include:
- Extreme fatigue
- Low blood pressure
- Fluid buildup in the lungs
- Trouble breathing
- Kidney damage
- Heart attacks
- Intestinal bleeding
- Diarrhea or abdominal pain
- High fever and chills
- Rapid heart beat
- Mental changes
These side effects are often severe and, rarely, can be fatal. Only doctors experienced in the use of these cytokines should give this treatment.
Interferon has less serious side effects than IL-2, but it does not seem to be as effective when used by itself. It is more often used in combination with the targeted drug bevacizumab (Avastin).
Common side effects of interferon include flu-like symptoms (fever, chills, muscle aches), fatigue, and nausea.
Immune checkpoint inhibitors
An important part of the immune system is its ability to keep itself from attacking normal cells in the body. To do this, it uses “checkpoints,” which are molecules on immune cells that need to be turned on (or off) to start an immune response. Cancer cells sometimes use these checkpoints to avoid being attacked by the immune system. But newer drugs that target these checkpoints hold a lot of promise as cancer treatments.
Nivolumab (Opdivo) is a drug that targets PD-1, a protein on immune system cells called T cells that normally helps keep these cells from attacking other cells in the body. By blocking PD-1, this drug boosts the immune response against cancer cells. This can shrink some tumors or slow their growth.
This drug can be used in people whose kidney cancer starts growing again after other drug treatments.
This drug is given as an intravenous (IV) infusion, typically every 2 weeks.
Possible side effects
Side effects of immune checkpoint inhibitors can include fatigue, cough, nausea, itching, skin rash, loss of appetite, constipation, joint pain, and diarrhea.
Other, more serious side effects occur less often. These drugs work by basically removing the brakes on the body’s immune system. Sometimes the immune system starts attacking other parts of the body, which can cause serious or even life-threatening problems in the lungs, intestines, liver, hormone-making glands, kidneys, or other organs.
It’s very important to report any new side effects to your health care team promptly. If serious side effects do occur, treatment may need to be stopped and you may get high doses of corticosteroids to suppress your immune system.
Newer approaches to immunotherapy
Cytokines can also be used as part of some experimental immunotherapy techniques. In one approach, immune system cells are removed from the blood and treated with cytokines in the lab to help activate them. These cells are then injected back into the patient in the hope that this will stimulate the immune system to fight the cancer.
In recent years, newer types of drugs that help boost the body’s immune response against cancer cells have shown early promise in kidney cancer. These and other newer forms of immunotherapy are described in “What’s new in kidney cancer research and treatment?”
Last Revised: 02/10/2016