For people who have advanced non-small cell lung cancer (NSCLC) or early stage or metastatic triple-negative breast cancer, doctors may consider a treatment type called immunotherapy. Immunotherapy is a relatively new cancer treatment used to help a person’s immune system to kill cancer16.
The immune system’s ability to detect and destroy abnormal cells usually prevents cancers from developing. However, some cancer cells elude detection by the immune system and thus lead to the inability of the immune system to recognize and destroy those cancer cells16. The immune system functions through a balanced and controlled process to attack foreign elements but also by having the ability to keep itself from attacking normal cells in the body.
Immune cells have “checkpoint proteins” on their surfaces which act like switches that need to be turned on (or off) to start an immune response (against abnormal cells) or to stop an immune response (against normal cells). Cancer cells sometimes use these checkpoints to avoid being attacked by the immune system16. Drugs that target checkpoint proteins on immune cells (called checkpoint inhibitors) can be used to treat some people with NSCLC16. Checkpoint inhibitors can also be used with chemotherapy to treat triple-negative breast cancer and has been shown to improve survival outcomes in patients37. Immunotherapy can be used by itself or in combination with traditional chemotherapy.
For doctors to know if immunotherapy can be prescribed to a patient, a type of testing performed on the cancer cells known as biomarker testing is required. Patients who possess biomarkers for immunotherapy derive the most benefit from its use. If you are unsure if you are a candidate for immunotherapy, ask your doctor if it is a suitable treatment option for you.
Recent advancements have also demonstrated that immunotherapy can improve survival outcomes for certain patients, compared to chemotherapy alone. This tailored-to-fit approach has significantly changed the cancer treatment model to improve patient outcomes37,42.
How Checkpoint Inhibitors Work16
Cancer cells sometimes disguise themselves or block the immune system. The immune system controls activity of the cancer-fighting lymphocytes, called T cells, through a pathway known as ‘PD-1’. But some cancer cells block T cell attack by taking control of the pathway.
PD-1 is a checkpoint protein on T cells. It normally acts as an “off switch” that helps keep the T cells from attacking other cells in the body by attaching (binding) to its target called PD-L1, a protein present on some normal (and cancer) cells. When this PD-1 to PD-L1 binding happens, a signal is sent to stop the T cell from attacking the other cell. Some cancer cells possess large amounts of PD-L1 and are therefore able to avoid T cell attack. These cancer cells are then free to grow and metastasize.
Understanding if Immunotherapy is Right for You43
Immunotherapy is not for everyone. When considering immunotherapy, your doctor will evaluate your cancer type, approved immunotherapy indications for that subtype, and your medical history before recommending the most suitable course of action for you. Your doctor may ask:
- If you have any existing autoimmune conditions (e.g. lupus, rheumatoid arthritis, or Crohn’s disease).
- If you have had a prior organ transplant.
- If you have any chronic liver diseases.
- You to provide an overview of your liver health history.
- If you are taking any other medications (e.g. steroids and other prescription medicine, non-prescription medicine such as vitamins and herbal supplements).
For more information, please click here for other lung cancer treatment types and here for other triple-negative breast cancer treatment types.