Cancer has likely been around as long as humans have. But over the years, our ability to test for the disease and treat it has greatly improved. More people who get cancer are living longer. Some are being cured.
Exciting advances are paving the way to better treatments and possibly more cures.
Your immune system hunts down and kills invaders like bacteria and viruses. It also seeks out and destroys cancers as they form. But cancer has developed ways to hide from your immune system. It can grow despite your body’s efforts to stop it.
Immunotherapy helps your immune system attack the cancer. This treatment works in several ways, including:
- Preventing the cancer from hiding
- Boosting your immune response against cancer
There are several immunotherapy treatments in the works right now:
Checkpoint inhibitors. Your immune system has fighters called T cells. They seek and destroy foreign cells, including cancer. Healthy cells have proteins called checkpoints on their surface that let the fighters know they're friendly.
Cancer cells sometimes use checkpoints to hide from your immune system.
Immunotherapy drugs called checkpoint inhibitors block checkpoints on cancer cells to help T cells find the cancer. Checkpoint inhibitors treat several types of cancer, including bladder, colorectal, head and neck, kidney, liver, lung, lymphoma, melanoma, and stomach.
Monoclonal antibodies. Your immune system makes proteins called antibodies to help it spot invaders like bacteria and viruses. Each antibody seeks out another protein, called an antigen, on the surface of an invading cell.
Monoclonal antibodies are designed in a lab to target antigens on cancer cells. Some help your immune system find the cancer. Others are attached to a toxic substance that kills the cancer.
Adoptive cell transfer. This method uses your own immune cells to treat your cancer. Doctors take the cells from your blood or tumor. They modify them in a lab so they will be better able to bind to and attack cancer cells. Chimeric antigen receptor, T-cell (CAR T-cell) therapy, is one type. It’s approved to treat certain kinds of leukemia and lymphoma.
Immune system modulators. They boost your body's immune response against the cancer. An example is cytokines -- substances that control immune cells' growth and activity. Examples include:
- Interleukins,which help immune cells communicate with each other
- Interferons,which activate cancer-fighting immune cells
Cancer vaccines. Just like vaccines help your body find measles or polio viruses, cancer vaccines help your immune system find cancer cells.
Vaccines that treat existing cancer are called therapeutic vaccines. These vaccines may be made from your cancer cells. Doctors take them out of your body and use them to make the vaccine. Once it’s ready to help your cells find and attack the cancer, it goes back into your body.
One cancer vaccine, sipuleucel-T (Provenge), is used to treat some prostate cancer that has spread. Two others that have been approved are talimogene laherparepvec (T-VEC), for some advanced melanoma skin cancers and TICE BCG for some bladder cancers. Other vaccines against breast, lung, and brain cancers are being studied in clinical trials.
Preventive vaccines can protect against the formation of cancer and guard against human papillomavirus (HPV) and hepatitis B, which can lead to liver cancer.
Finding an effective cancer vaccine has proven more difficult than researchers had thought. Because cancer cells have many ways to hide from your immune system, they can be hard to track down.
Researchers are now looking at more effective ways to give cancer vaccines. One method is to combine them with substances called adjuvants to help them work better.
Cancer research no longer follows a one-size-fits-all approach. It's become much more personalized, with research on genes driving the trend.
Doctors now know that one cancer -- like breast or lung cancer -- can come in many different genetic types.
Genomics, the study of changes to genes in your DNA, is giving doctors important clues about how your cancer will act and how to best treat it. Doctors look for changes called mutations in certain cancer genes.
Finding these mutations can help them:
- Diagnose the cancer
- Predict your outcome
- Determine which drug or other treatment will work best on the cancer
- See how well the treatment is working
Gene-based treatments work for people with specific gene changes in the cancer. For example, the drugs vemurafenib (Zelboraf), dabrafenib (Tafinlar), and encorafenib (Braftovi) treat people with melanoma who have a gene mutation known as BRAF. The drugs stop the overproduction of BRAF protein that the mutation causes. Trastuzumab (Herceptin) works the same way against breast cancers that overproduce the HER2 gene.
Scientists are studying new treatments based on gene changes in cancer cells. These studies could lead to even more targeted gene therapies in the future.
Will There Be a Cure?
Part of the challenge in curing cancer is that it isn't one disease, but hundreds of different diseases. A lot of research needs to be done, and it takes time. But scientists have made great strides.
If you've been diagnosed with cancer, visit a National Cancer Institute-designated center, where you'll get access to the latest treatments. You can also enroll in a clinical trial. Doctors test new cancer treatments in clinical trials before they are available to the public.