Immunotherapy is used to stimulate the body's immune system against cancer. These treatments target specific genetic characteristics of the tumor cells. The genetic characteristics of tumors do not depend on what organ in the body the cancer develops. So these medications may be effective against many types of cancer. (See also Cancer Treatment Principles.)
There are several different types of treatments that doctors use to stimulate the immune system. And this area of cancer treatment is being intensively studied. The National Cancer Institute maintains an up-to-date list of immunotherapy medications (as well as other medications used to treat cancer). The list provides a brief summary of each medication's uses and links to additional information.
Monoclonal antibodies
Trastuzumab enhances the effect of chemotherapy agents.
Rituximab linked to a radioactive isotope can be used to deliver radiation directly to lymphoma cells.
Several monoclonal antibodies modify the function of immune checkpoints
Modified T cells
T cells are cells of the immune system that can recognize and destroy foreign cells. In this form of cancer treatment, T cells are removed from the blood of a person with cancer. Then in the laboratory, doctors modify these T cells genetically so that they recognize and attack that person's cancer cells. Then they return the modified T cells to the person. The most common example of this strategy is termed chimeric antigen receptor (CAR)-T-cells. CAR-T-cells are an effective therapy in people with acute lymphoblastic leukemia, B-cell lymphomas, and multiple myeloma.
Related techniques involve growing the extracted T cells in the laboratory and activating them by exposure to a certain substances (cytokines) which expand their numbers and potentially increase their ability to kill cancer cells when re-infused.
Nonspecific immunotherapy
Biologic response modifiers stimulate normal cells to produce chemical messengers (mediators) that improve the immune system's ability to find and destroy cancer cells. The effects are generalized and not specific to only certain cancers.
Interferon (of which there are several types) is the best-known and most widely used biologic response modifier. Almost all human cells produce interferon naturally, but interferon can also be made through biotechnology. Although its precise mechanisms of action are not totally clear, interferon has a role in the treatment of several cancers, such as Kaposi sarcoma and malignant melanoma.
Interleukins are messengers produced by certain immune system cells (activated T cells). Giving interleukins can help in the treatment of metastatic melanoma and may be of benefit in kidney cancer. Interleukin 2, which is produced by certain white blood cells, can be helpful in renal cell carcinoma and metastatic melanoma.
Vaccines for cancer
Vaccines composed of material derived from cancer cells can boost the body's production of antibodies or immune cells that can attack the cancer. Extracts of weakened tuberculosis bacteria, which are known to boost the immune response, have been successful when instilled into the bladder to prevent recurrence of bladder tumors.
