Immunotherapy is being used more often for treating certain cancers. You may have heard this term and wondered exactly what this means.
In a nutshell, immunotherapy uses your immune system to fight cancer and other diseases. While traditional cancer therapies directly attack the cancer cells, they can also damage to surrounding healthy normal cells. Immunotherapies, on the other hand, harness the body’s own defense system to battle cancer.
Madappa Kundranda, MD, PhD, a medical oncologist at Banner MD Anderson Cancer Center in Gilbert, Ariz., explains:
“The body’s immune system is a complex system that is intricately designed to fight cancer cells. To balance this, and prevent the body from accidentally attacking itself, there is a system of checkpoints (like brakes). Cancer cells exploit this system by using a variety of tactics to keep the ‘brakes’ on and prevent the immune system from recognizing and/or attacking them,” Dr. Kundranda said.
“In recent years, there has been tremendous success using the rather novel approach of an immune checkpoint blockade. This involves using drugs that can weaken the signal the cancer cell sends out in order to prevent the body’s own immune mechanism to fight it. If the cancer cell were a car with defective brakes that are stuck in the ‘on’ position, these novel drugs help in cutting that ‘brake’ and allowing the ‘accelerator’ (the body’s own immune system) to kill the cancer cells,” he said.
Checkpoint blockade drugs have been approved for melanoma, lung and kidney cancer. Clinical trials for many other cancer types are also being conducted.
In addition to checkpoint blockade, there are other types of treatments that target the immune system rather than tumors directly. These include:
- Adoptive Cell Therapy: in clinical trials now, this therapy relies either on taking immune system warriors called T cells from patients, expanding them to billions in the lab, and giving them back to the patient or genetically engineering those T cells to attack a specific target on cancer before reintroducing them into the patient’s body.
- Therapeutic cancer vaccines: therapeutic cancer vaccines designed to stimulate the patient’s own immune system against tumor antigens.
- Monoclonal antibodies: tumor-specific monoclonal antibodies that can trigger a direct or indirect immune response that leads to destroying the cancer cell.
Immunotherapy doesn’t have the same type of negative side effects as conventional therapy and can potentially provide a durable response, even in aggressive cancers, Dr. Kundranda said. However, the side effects of this treatment are related to the hyper-immune system and can be life-threatening if not recognized early and treated.
As always, talk to your physician about which treatment options are the best for you and your situation.