What’s new in melanoma skin cancer research?
Research into the causes, prevention, and treatment of melanoma is being done in many medical centers around the world.
Causes, prevention, and finding melanoma early
Sunlight and UV rays
Recent studies suggest there may be 2 ways that UV rays causes melanoma. The first way is linked to a lot of sun exposure and sunburns as a child or teen. This early sun exposure may cause changes in the DNA of skin cells that starts them on a path to becoming melanoma cells many years later. Some doctors think this is why melanomas often start on the legs and trunk – places that aren’t often exposed to the sun in adulthood.
The second link is to melanomas that start on the arms, neck, and face. These areas are often exposed to sun, particularly in men. Tanning booths may also aid either kind of melanoma start.
Researchers are looking to see how melanomas that start as a result of these types of UV exposure may differ. For instance, they may have different gene changes that would mean they should be treated differently.
Most skin cancers can be prevented. The best way to reduce the number of skin cancer cases is to educate the public, especially parents, about skin cancer risk factors and warning signs.
It is also important to find melanoma early, when it is most likely to be completely cured. Check your skin every month and be aware of the warning signs of melanoma.
The American Academy of Dermatology (AAD) sponsors free skin cancer screenings around the country every year. Many local American Cancer Society offices work with the AAD to help with these screenings. The phone number and Web address for the AAD are listed in the “How can I learn more?” section.
Along with recommending staying in the shade, the American Cancer Society uses the slogan, “Slip! Slop! Slap! ... and Wrap.” It is a catchy way to remind yourself to slip on a shirt, slop on sunscreen, slap on a hat, and wrap on sunglasses when you are going to be outdoors.
Scientists have made a lot of progress during the past few years in learning how UV light harms DNA. But some inherited changes in DNA can make a person more likely to get melanoma. People who have a strong family history of melanoma should talk to a cancer genetic counselor or a doctor who knows about cancer genetics to discuss the pros and cons of genetic testing.
Advances in research are also being used in staging cancer. Very sensitive new tests can better find the spread of melanoma to lymph nodes. These tests might help doctors know which patients could be helped with treatments like immunotherapy after surgery. But some doctors worry that this test can sometimes suggest that a person has cancer when they really don’t. For now, the test is only being used in research studies.
Early-stage melanomas can often be cured with surgery, but more advanced melanomas are often much harder to treat because standard cancer treatments such as chemotherapy don’t work very well. Newer types of treatment have shown a great deal of promise in treating more advanced melanomas.
Drugs that block PD-1 and PD-L1
Melanoma cells may use natural pathways in the body to help avoid the immune system. For instance, they often have a protein called PD-L1 on their surface that helps them evade the immune system. New drugs that block the PD-L1 protein (or the PD-1 protein on immune cells called T cells) can help the immune system spot the melanoma cells and attack them. Studies of these new drugs are now being done.
Weakened melanoma cells (or certain substances found in these cells) can be given to a patient to try to make the body’s immune system kill the cancer cells. This is something like the way we use vaccines to destroy viruses that cause polio, measles, and mumps. But making a vaccine against a tumor like melanoma is harder than making a vaccine to fight a virus. Clinical trials are going on to test the value of treating people with advanced melanoma with vaccines, sometimes combined with cytokine therapy as well. The results of these studies have been mixed so far, but newer vaccines may hold more promise.
Other forms of immunotherapy are also being studied. Some early studies have shown that treating patients with high doses of chemotherapy and radiation therapy and then giving them immune system cells found in tumors can shrink melanoma tumors and perhaps prolong life as well.
Another potential approach to treatment is to combine different types of immunotherapy, which may be more effective than any single treatment for advanced melanoma.
New drugs that attack gene changes in melanoma cells are being studied.
A gene called BRAF is changed in the cells of about half of all melanomas. Drugs that target this gene are being developed and studied in clinical trials. Vemurafenib (Zelboraf) is one of these drugs that has been in use since last year. Recently, another drug that targets BRAF gene changes, dabrafenib (Tafinlar®), was also approved to treat advanced melanoma.
The MEK gene is in the same signaling pathway inside cells as the BRAF gene. Trametinib (Mekinist™) is a drug that blocks MEK. It has been shown to cause some melanomas with BRAF mutations to shrink, and was recently approved by the Food and Drug Administration for advanced melanoma.
An approach now being studied is to combine a BRAF drug with a MEK drug in the hope of causing tumors to shrink for a longer time.
Certain types of melanomas sometimes have changes in a gene called c-kit. Some targeted drugs are already used to treat other cancers with changes in c-kit. Clinical trials are now looking to see if these drugs might help people with these types of melanoma.
Several other drugs that target other abnormal genes or proteins are now being studied in clinical trials as well.
Last Medical Review: 09/26/2012
Last Revised: 05/30/2013