Cancer treatments like chemotherapy and radiation rely on drugs or high-energy X-rays to kill cancer cells. Immunotherapy is different, because it uses your own immune system to fight off the cancer.
Some immunotherapy treatments help your immune system find the cancer or work harder to attack it. Others give you man-made versions of proteins or other immune substances to help your body fight the disease.
Today, immunotherapy is approved to treat certain kinds of cancer -- like melanoma, lymphoma, and lung cancer. Immune-based treatments for many other types of cancer are being tested in clinical trials.
How Do Doctors Use Immunotherapy?
It’s a pretty new treatment compared with surgery, radiation, and chemotherapy. It's approved to treat some cancers, but not others. And it works better on some forms of the disease than others.
Depending on the type of cancer you have, you might get immunotherapy:
- With or after another treatment, like surgery, radiation, or chemotherapy
- By itself as a first treatment
- As part of a clinical trial if other treatments haven't worked and your cancer has spread
Types of Immunotherapy and Cancers They Treat
Whether you get immunotherapy depends on the type of cancer you have, and how well other treatments have worked. Here's a rundown of the different types, and which cancers they're approved to treat.
Your immune system makes proteins called antibodies. They find and attach to other proteins called antigens on the surface of foreign cells in your body. Once the antibodies are in place, they tell your immune system to launch an attack against the foreign cells.
Monoclonal antibodies are man-made versions of antibodies. They seek out and attach to antigens on the surface of cancer cells. Their job is to find cancer cells so your immune system can destroy them. Sometimes they can deliver cancer-killing medicine straight into the cancer cells.
Examples of monoclonal antibodies and the cancers they treat:
- Alemtuzumab (Campath) -- chronic lymphocytic leukemia (CLL)
- Bevacizumab (Avastin) -- cervical, colorectal, non-small-cell lung, kidney, and some brain cancers
- Rituximab (Rituxan) -- non-Hodgkin's lymphoma
- Trastuzumab (Herceptin) -- breast and stomach cancers
Your immune system has to tell your body's own cells apart from foreign invaders so it knows which ones to attack. Normal cells have substances called checkpoints on their surface that tell your immune system to leave them alone.
Cancer cells also use checkpoints to stay under the radar. Immunotherapy drugs called checkpoint inhibitors help your immune system spot these cells so they can't hide.
Checkpoint inhibitors and the cancers they treat include:
- Atezolizumab (Tecentriq) -- non-small-cell lung cancer, bladder cancer
- Ipilimumab (Yervoy) -- melanoma that has spread or that might come back after surgery
- Nivolumab (Opdivo) -- bladder cancer, head and neck cancer, Hodgkin's lymphoma, kidney cancer, non-small-cell lung cancer, melanoma
- Pembrolizumab (Keytruda) -- non-small-cell lung cancer, head and neck cancer, melanoma
Like the shots that protect you against the flu and measles, cancer vaccines help your immune system recognize and defend your body against cancer. Some vaccines help prevent cancer. Others treat cancer or stop it from coming back.
The only approved vaccine to treat cancer is sipuleucel-T (Provenge). Doctors use it on prostate cancer that continues to spread after hormone therapy. Other vaccines are being tested in clinical trials.
Other types of immunotherapy
A few other immunotherapy treatments don't target cancer cells directly. Instead, they boost your immune system to make it more effective against cancer.
Examples of these treatments include:
- Bacille Calmette-Guérin -- early-stage bladder cancer
- Imiquimod (Zyclara) -- early-stage skin cancer
- Interleukin-2 (IL-2) -- kidney cancer and melanoma that have spread
- Interferons (IFN-alpha, IFN-beta, IFN-gamma) -- some types of leukemia and lymphoma, kidney cancer, melanoma, Kaposi sarcoma
- Lenalidomide (Revlimid), pomalidomide (Pomalyst), thalidomide (Thalomid) -- multiple myeloma
Should I Try Immunotherapy?
This type of treatment isn't right for everyone. It doesn't work on all types of cancer. And if surgery, radiation, or chemotherapy has stopped your cancer from growing, you might not need it.
Immunotherapy might be for you if it's approved for your cancer. Even if it isn't, you still might be able to get it in a clinical trial if your first treatments didn't work. Ask your doctor if any trials are testing out new immunotherapy treatments for your cancer type.
Here are questions to ask your doctor to decide if immunotherapy is right for you:
- Are any immunotherapy treatments approved for my cancer?
- If not, are any clinical trials testing these treatments for my cancer?
- How might it help my cancer?
- Will I get it alone, or with other treatments?
- How will I get it (by shot, etc.)?
- How often will I need it?
- What kinds of side effects can it cause?
- For how long will I need to take it?
- What happens if it doesn't work?
Make sure you understand how immunotherapy might help you and what side effects it can cause before you start treatment.