There are several treatments for metastatic renal cell carcinoma (RCC), including surgery, targeted treatment, and chemotherapy.

But in some cases, you might stop responding to targeted therapy. Other times, targeted therapy drugs might cause severe side effects or allergic reactions.

If this happens, your doctor may recommend another form of treatment called immunotherapy. Here’s a detailed look at what immunotherapy is, and whether it’s right for you.

Immunotherapy is a type of cancer treatment that uses natural and artificial substances to change the way the cells in your body behave. Some types of immunotherapy work to fight off or destroy cancer cells. Others strengthen or boost your immune system and help to manage the symptoms and side effects of your cancer.

There are two main types of immunotherapy treatments for metastatic RCC: cytokines and checkpoint inhibitors.

Cytokines are man-made versions of proteins in the body that activate and boost the immune system. The two cytokines most often used to treat kidney cancer are interleukin-2 and interferon-alpha. They have been shown to help shrink kidney cancer in a small percentage of patients.

Interleukin-2 (IL-2)

This is the most effective cytokine for treating kidney cancer.

High doses of IL-2, however, can cause severe and sometimes fatal side effects. These side effects include fatigue, low blood pressure, trouble breathing, fluid buildup in the lungs, intestinal bleeding, diarrhea, and heart attacks.

Due to its potentially high-risk nature, IL-2 is usually only given to people who are healthy enough to withstand the side effects.

Interferon-alfa

Interferon-alfa is another cytokine sometimes used to treat kidney cancer. It’s typically given as a subcutaneous injection three times a week. Its side effects include flu-like symptoms, nausea, and fatigue.

While these side effects are less severe than IL-2, interferon isn’t as effective when used by itself. As a result, it’s often used in combination with a targeted drug called bevacizumab.

Your immune system prevents itself from attacking normal cells in your body by using “checkpoints.” These are molecules on your immune cells that need to be turned on or off to start an immune response. Cancel cells sometimes used these checkpoints to avoid being targeted by the immune system.

Checkpoint inhibitors are drugs that target such checkpoints. They help keep your immune system’s response to cancer cells in check.

Nivolumab (Opdivo)

Nivolumabis an immune checkpoint inhibitor that targets and blocks PD-1. PD-1 is a protein on your immune system’s T cells that prevents them from attacking other cells in your body. This helps to boost your immune response against cancer cells and can sometimes decrease the size of tumors.

Nivolumab is typically given intravenously once every two weeks. It’s a viable option for people whose RCC has started growing again after using other drug treatments.

Ipilimumab (Yervoy)

Ipilimumab is another immune system inhibitor that targets the CTLA-4 protein on T cells. It’s given intravenously, usually once every three weeks for four treatments.

Ipilimumab can also be used in combination with nivolumab. This is for people with advanced kidney cancer who haven’t yet received treatment.

This combination has been shown to significantly increase overall survival rates. It’s generally given in four doses, followed by a course of nivolumab on its own.

The data from this study published in the New England Journal of Medicine demonstrated a favorable 18-month overall survival rate with the combination treatment of nivolumab and ipilimumab.

On April 16, 2018, the FDA approved this combination for the treatment of people with poor- and intermediate-risk advanced renal cell carcinoma.

Potential side effects

The most common side effects of immune checkpoint inhibitors are fatigue, skin rash, itching, and diarrhea. In rare cases, PD-1 and CTLA-4 inhibitors can lead to serious organ problems that may become life-threatening.

If you’re currently receiving immunotherapy treatment with one or both of these drugs and start to experience any new side effects, report them to your doctor immediately.

The treatment you and your doctor will decide on depends on several factors. If you’re living with metastatic RCC, talk with your doctor about your treatment options.

Together, you can discuss whether it might be a viable treatment path for you. They can also speak with you about any concerns you have about side effects or the length of treatment.