If you or someone you love recently received a breast cancer diagnosis, you’re probably concerned and researching all the possible treatment options. The good news is that physicians and scientists have been researching new treatments long before you received your diagnosis, including immunotherapy for breast cancer.
“In recent years, we’ve been learning more about cancer as well as cancer treatments,” says Dr. J. Eric Turner, a board-certified and fellowship-trained medical oncologist at Beaufort Memorial Oncology Specialists. “We’re gaining a better understanding of how cancers act in the body, and newer immunotherapy treatments have allowed us to train the body to attack cancers in ways that traditional forms of treatments can’t.”
Read More: Your Immune System and Cancer: What’s the Connection?
Understanding Immunotherapy
Immunotherapy works by training your body’s immune system to recognize and destroy cancer cells the same way it does viruses, bacteria and other foreign invaders.
Breast cancer cells, like all cancer cells, are mutated versions of healthy cells. Because the cells started out healthy, your immune system doesn’t always recognize them as harmful and attack them. As cancer cells grow, they may form proteins on their surface, undergo genetic changes or have other alterations that make it even harder for your immune system to find them.
“The types of immunotherapy for breast cancer currently in use teach the immune system to identify some of the cellular changes that occur as breast cancer cells grow,” Dr. Turner says. “In many cases, they can help breast cancer patients whose cancers haven’t responded to traditional breast cancer treatments. Sometimes, they’re used in combination with chemotherapy, radiation therapy or surgery.”
Below are some of the Food and Drug Administration-approved immunotherapies for breast cancer:
- Immune checkpoint inhibitors teach your immune system to identify proteins that breast cancer cells create as they grow. Healthy immune cells called T cells have proteins of their own that identify and can attach to harmful proteins on breast cancer cells. When this happens, the immune system gets a signal not to attack the cancer cell. Immune checkpoint inhibitors keep the T cells from attaching to the harmful cells, allowing the immune system to fight cancer.
- Targeted therapies for breast cancer train the immune system to recognize proteins and other targets on cancer cells, allowing the immune system to either attack them, stop them from growing or stop them from spreading. Monoclonal antibodies, which got a lot of attention as a treatment for COVID-19, is a form of targeted therapy used to treat many types of cancer, including breast cancer.
CAR T-cell therapy is another form of immunotherapy approved only to treat certain blood cancers, but it is being researched as a treatment for breast cancer. In CAR T-cell therapy, T cells are collected from your body and sent to a laboratory to be modified in ways that make them better at identifying and destroying cancer cells. The cells are injected back into your body to fight cancer.
Types of Breast Cancers Treated With Immunotherapy
Because many immunotherapies are so new, doctors are often selective about who benefits and when they should be used. In most cases, they are used for more advanced cancers.
“Immune checkpoint inhibitors have been found to be effective on triple-negative breast cancers,” Dr. Turner says. “Monoclonal antibodies may be successful for treating women with HER2-positive breast cancer. But we really approach immunotherapy on a case-by-case basis.”
Immunotherapies aren’t always better than traditional treatments, such as chemotherapy, but they can be used in combination with those treatments to improve a patient’s outlook.
Read More: It Takes a Team: Cheryl Fields and Her Breast Cancer Journey
Because immunotherapies can affect the immune system, the side effects can be significant. Side effects will also vary based on the type of medication used. Some common side effects include appetite loss, difficulty breathing, constipation, diarrhea, fatigue, nausea and rash. Immunotherapies can also impact organs, such as the liver and kidneys.
Despite these potential side effects, immunotherapies could significantly improve care for some breast cancer patients. At Beaufort Memorial, we participate in clinical trials that allow patients access to treatments, including immunotherapies, still in the research phase.
“Immunotherapies offer a lot of potential benefit, but there are still many unknowns,” Dr. Turner says. “If they give someone with breast cancer hope at a better outcome, we want them to be available as long as they’re appropriate for that patient.”
Beaufort Memorial offers immunotherapy at both of our cancer centers. Find a medical oncologist close to you at the Keyserling Cancer Center in Beaufort or New River Cancer Center in Okatie.
