Just like bacteria or viruses which are attacked and destroyed by the immune system because they are “foreign” to the body, cancer cells are at first recognized as dangerous by the body’s own immune system. However eventually cancer cells develop the ability to by pass or turn off the immune system defense.
Immunotherapy medications use a person’s own immune system to fight the cancer cells. They may stimulate, boost, or train a person’s own immune system to work better and harder when attacking cancer cells. This can done in one of the following two ways:
- Through immunization of the patient by administering a cancer vaccine, in which case the patient’s own immune system is trained to recognize tumor cells as targets to be destroyed, or
- Through the administration of therapeutic antibodies as drugs, in which case the patient’s immune system is recruited to destroy tumor cells by the therapeutic antibodies.
In cancer cases where immunotherapy is recommended, these treatments are more effective and less toxic than chemotherapy.