Genetic tests on your melanoma cells

Your doctors might look to see if your melanoma cells have changes (mutations) in certain genes, such as the BRAF V600 gene. This information can help doctors decide which treatment is best for you if you need targeted cancer drugs or immunotherapy.

About the test

A doctor looks to see if the melanoma cells have changes (mutations) in certain genes, such as the BRAF V600 gene. About 40 to 50 out of every 100 people with melanoma skin cancers (40 - 50%) have this gene change. The change to the gene cause it to make an overactive BRAF protein. This makes cells grow and divide too fast.  

If you have changes in the BRAF gene, doctors describe your melanoma as BRAF positive. If you don’t have changes, then your melanoma is BRAF negative.

Why you might have this test

Your doctors might do genetic testing on your melanoma if you have stage 2C, stage 3 or stage 4 melanoma. 

The results of these tests help doctors decide which type of targeted cancer drug might help you if you need this type of treatment.

What happens

You might not need any extra tests. The doctor can sometimes do genetic tests on your melanoma cells that were removed during surgery.

But sometimes the doctor needs to take another sample of your melanoma. They will tell you more about this, and about what the test will involve. 

Last reviewed: 
30 Apr 2020
Next review due: 
28 Apr 2023
  • Melanoma assessment and management
    National Institute for Health and Care Excellence, July 2015

  • The role of BRAF V600 mutation in melanoma
    PA Ascierto and others
    Journal of Translational Medicine, 2012 Volume 10, Issue 1