What Is Immunotherapy for Cancer?
Immunotherapy (sometimes called biologic therapy) is a type of treatment that helps a person's immune system fight cancer. It can stop or slow the growth of cancer cells. It may also help the immune system work better at destroying cancer cells.
Children with cancer may get immunotherapy (im-yuh-know-THER-uh-pee) along with other types of treatment, like chemotherapy and radiation therapy.
What Does the Immune System Do?
The immune system is the body's defense against infectious organisms (like bacteria and viruses) and other invaders that cause disease. Through a series of steps called the immune response, the immune system attacks these invaders.
The immune system contains a network of cells, tissues, and organs that work together to protect the body. A type of white blood cell, called a lymphocyte, is an important part of the body's defense system. Lymphocytes travel between organs like the spleen, tonsils, and lymph nodes. They recognize foreign invaders in the body and destroy them.
What Are the Types of Immunotherapy?
Types of immunotherapy doctors use to fight cancer include:
- Antibody-drug conjugates (monoclonal antibodies). These manmade antibodies (disease-fighting proteins) help the immune system work by trying to attach to specific targets (markers) found on cancer cells. Some monoclonal (mah-nuh-KLO-nul) antibodies mark cancer cells so that they will be better seen and then destroyed by the immune system.
- Non-specific immunotherapies. These boost the immune system in a general way, helping it attack cancer cells.
- Oncolytic (ahn-kuh-LIT-ik) virus therapy. Some viruses (called oncolytic viruses) can be changed in a laboratory so they infect and kill cancer cells. They also can help alert the immune system to fight the cancer cells.
- Cancer vaccines. These vaccines don't prevent diseases, as the flu and chickenpox vaccines do. Instead, they work against cancer by increasing the immune system's response to cancer cells in the body.
- CAR T-cell therapy. Doctors take some T-cells (a type of white blood cell) from a patient's blood and change them in a lab so they can find and destroy cancer cells. Then, doctors put these changed T-cells back into the patient's body.
- Bi-specific T-cell engagers (BiTE). These manmade antibodies can link a T-cell to a tumor cell. When the two cells are linked, the T-cell kills the tumor cell.
Who Gets Immunotherapy?
Doctors use immunotherapy for specific types of cancer, such as leukemia, lymphoma, kidney cancer, and others.
In children, immunotherapy isn't used as a first-line treatment. If a child's cancer isn't cured with the usual treatment, the care team decides if the type of cancer may respond to immunotherapy.
How Is Immunotherapy Given?
Doctors give immunotherapy in the way that is best for the patient's condition. These include:
- intravenous (IV): the treatment is put into a vein
- oral (by mouth): pills or liquid are swallowed
- topical (on the skin): the cream is rubbed into the skin for some types of early skin cancer
What Are the Risks of Immunotherapy?
Side effects can vary between the different types of immunotherapy and the kinds of cancer they treat. The side effects can be mild to severe.
Common side effects include:
- fever
- tiredness
- nausea and vomiting
- muscle aches
- pain
- skin rashes
- shortness of breath
- headaches
- swelling
- hormone changes
- inflammation (redness and swelling)
Looking Ahead
Immunotherapy holds promise for fighting cancer. It's too early to know if it could become a first-line treatment. If it does, this means it could be used first to treat cancer rather than chemotherapy or radiation therapy.