Targeted therapy for melanoma skin cancer
Some people with melanoma skin cancer have targeted therapy. It uses drugs to target specific molecules (such as proteins) on cancer cells or inside them. These molecules help send signals that tell cells to grow or divide. By targeting these molecules, the drugs stop the growth and spread of cancer cells and limit harm to normal cells. Targeted therapy may also be called molecular targeted therapy.
You may have targeted therapy to:
- stop or control the growth and spread of cancer cells
- shrink a tumour
- relieve pain or control the symptoms of advanced melanoma skin cancer (called palliative therapy)
Your healthcare team will consider your personal needs to plan the drugs, doses and schedules of targeted therapy. You may also receive other treatments.
Targeted therapy drugs used for melanoma skin cancer @(Model.HeadingTag)>
About half of all melanoma skin cancers have changes (mutations) in the BRAF gene, specifically a BRAF V600E or BRAF V600K mutation. The mutation alters the BRAF protein causing melanoma skin cancer cells to grow and divide out of control.
Mutations in the MEK gene and the C-KIT gene may also happen with melanoma skin cancer. But these happen much less often than BRAF gene mutations.
Most people with melanoma skin cancer that has spread to nearby lymph nodes or other parts of the body (locoregional or metastatic melanoma skin cancer) will have a sample of the cancer tested for the BRAF, MEK and C-KIT gene mutations. Melanoma skin cancers that test positive for any of these gene mutations may respond to certain targeted therapy drugs.
The following are the targeted therapy drugs used for metastatic melanoma skin cancer.
BRAF inhibitors target the BRAF protein directly to help shrink and control the growth of the melanoma skin cancer. The BRAF inhibitors used for melanoma skin cancer are:
- vemurafenib (Zelboraf)
- dabrafenib (Tafinlar)
MEK inhibitors control the growth of melanoma cells by blocking the MEK protein. Since the MEK protein is normally turned on (activated) by the BRAF protein, MEK inhibitors are another way to treat melanoma skin cancers with BRAF gene mutations. Sometimes a MEK inhibitor is combined with a BRAF inhibitor. The MEK inhibitors used for melanoma skin cancer are:
- cobimetinib (Cotellic)
- trametinib (Mekinist)
Targeted therapy drugs for melanoma skin cancer are taken as a pill by mouth (orally) daily. A BRAF inhibitor is usually combined with a MEK inhibitor. How long treatment is given depends on the type of drug used and how well the cancer responds to the treatment.
Side effects @(Model.HeadingTag)>
Side effects can happen with any type of treatment for melanoma skin cancer, but everyone’s experience is different. Some people have many side effects. Other people have few or none at all.
Targeted therapy attacks cancer cells but doesn’t usually damage healthy cells, so there are usually fewer and less severe side effects than with chemotherapy or radiation therapy. Chemotherapy and radiation therapy can damage healthy cells along with cancer cells.
If you develop side effects, they can happen any time during, immediately after or a few days or weeks after targeted therapy. Sometimes late side effects develop months or years after targeted therapy. Most side effects go away on their own or can be treated, but some side effects may last a long time or become permanent.
Side effects of targeted therapy will depend mainly on the type of drug or combination of drugs, the dose and your overall health. Some common side effects of targeted therapy for melanoma skin cancer are:
- skin problems, such as rash and dryness
- sensitivity to the sun
- muscle, bone and joint pain
- nausea and vomiting
- eye problems
- abnormal liver function
- swelling (edema)
Tell your healthcare team if you have these side effects or others you think might be from targeted therapy. The sooner you tell them of any problems, the sooner they can suggest ways to help you deal with them.
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American Society of Clinical Oncology. Melanoma. 2015: http://www.cancer.net/cancer-types/melanoma/view-all.
Cancer Care Ontario. Drug Monograph: Dabrafenib. 2016: https://www.cancercare.on.ca/toolbox/drugformulary/.
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National Comprehensive Cancer Network. NCCN Clinical Practice Guidelines in Oncology: Melanoma (Version 2.2016). 2016.
National Institutes of Health. Genetics Home Reference: BRAF. Bethesda, MD: US National Library of Medicine; 2016: https://ghr.nlm.nih.gov/gene/BRAF.
Princess Margaret Cancer Centre. Princess Margaret Cancer Centre Clinical Practice Guidelines: Melanoma. 2015: http://www.uhn.ca/PrincessMargaret/Health_Professionals/Programs_Departments/Melanoma_Skin_Oncology/Pages/clinical_practice_guidelines.aspx.