context: Immunotherapy is one of the newest treatment options for metastatic non-small-cell lung cancer. It's different from chemotherapy. Instead of attacking cells as they divide, it uses your immune system to kill cancer and stop cancer it from growing. Your immune system protects you from unfamiliar things in your body, like viruses and bacteria. Cancer cells often get past your defenses because they look a lot like your normal cells. Your immune system may not turn on when it runs into them. Some cancer cells can even turn parts of your immune system off, so they can multiply unchecked. Immunotherapy helps boost your immune system so it can âseeâ and kill cancer cells more effectively. What's Available and How Does It Work? There are a few types of immunotherapy. Checkpoint inhibitors: Your immune system knows when to kick into gear because of certain molecules attached to the outside surface of its germ-fighting cells. These molecules are âcheckpoints,â and when they're turned on, your body knows it's time to go after invaders. When they're turned off, nothing happens. These drugs work at checkpoints and fire up your immune system to destroy cancer cells. They can also keep a tumor from switching your immune system off. Imagine your immune system is a car. When you get immunotherapy drugs it's like taking your foot off the brakes so the car can go full speed ahead. There are four FDA-approved checkpoint inhibitor drugs. You take them through IV infusion every 2-3 weeks: Atezolizumab ( Tecentriq) Durvalumab ( Imfinzi) Nivolumab ( Opdivo) Pembrolizumab ( Keytruda) But when your immune system runs full throttle, there can be serious side effects. It could attack your lungs, intestines, liver, hormone-making glands, kidneys, or other organs. If this happens, your doctor will take you off the drug and give you corticosteroids. They'll quiet your immune system down again. The FDA has a few checkpoint inhibitors for other types of cancer. Right now clinical trials are under way to see if they will also treat non-small-cell lung cancer. Other studies are checking to see how combinations of the drugs work. They include: Avelumab Ipilimumab ( Yervoy) Cancer vaccines: Preventative vaccines work to make you immune from certain threats before they enter your body. Now doctors have started using vaccines to treat cancers that already exist inside you. These are called therapeutic vaccines. One way doctors use therapeutic vaccines is to take part of a tumor out of your body and remove the antigens from it. They mix those antigens with a substance that alerts your body to invaders and inject that mixture back into you. This tells your immune system that the cancer in your body is dangerous so it can attack it. The FDA hasn't approved any cancer vaccines as treatment for non-small-cell lung cancer. But it has approved them for both metastatic prostate cancer in men and metastatic melanoma. The vaccines that are in studies for non-small-cell lung cancer include: P10s- PADRE PF-06936308 CIMAvax GRT- C901, GRT- C902, and GRT- C903 GEN-009 Adoptive cell therapy: This type of immunotherapy is still in clinical trials for treating non-small-cell lung cancer. It has worked against certain types of leukemia and lymphoma. Your doctor takes T-cells out of your body and grows many more just like them in a lab. Those T-cells are put back inside you to give your body a stronger defense against your cancer. Other forms of adoptive cell therapy take ordinary T-cells and add a mix of antibodies and a T-cell receptor so they can better target your tumor cells and kill them. Is It Right for You? Your doctor may suggest immunotherapy if you're diagnosed with advanced non-small-cell lung cancer. You may be able to use it first. It's more likely that she'll suggest it as a second choice after you've already tried other options like chemotherapy.