Testing for gene mutations in lung cancer

Some lung cancers, such as non small cell lung cancer have changes in particular genes and proteins. These changes can be used as targets for specific drug treatments.

Genes are found on chromosomes within all cells. They tell the cell which proteins to make.

Diagram showing genes and chromosomes

Scientists can look at lung cancer samples in the laboratory and search for gene changes (mutations) that change the way the cancer grows.

Doctors use this information to plan the best treatment, based on the genetic type of the cancer. This is called targeted cancer treatment or personalised therapy.

Gene changes in lung cancer

Some non small cell lung cancers have changes in genes that make the cancer grow and divide, such as:

  • the epidermal growth factor receptor (EGFR) gene
  • the anaplastic lymphoma kinase (ALK) gene
  • the ROS1 gene

Your doctor might test for one or more of these genes before you start treatment.

To have these tests your cancer must be a non small cell lung cancer that has spread into the area around the lung or has spread elsewhere in the body (an advanced cancer). Or you might have this test as part of a clinical trial.

About the genetic mutation test

Doctors look for gene mutations from a tissue sample, usually taken using a needle biopsy. They usually test a sample they already have from your original cancer tests. Or they might use a biopsy from your operation if you had one.

The testing is done in the laboratory. 

Another test that looks for gene changes in cells is the FISH test. FISH stands for fluorescence in situ hybridisation. 

Research has found that some targeted cancer drugs work well for some people with certain gene mutations in non small cell lung cancer. These drugs change the way that cells work and they help the body to control the growth of cancer.

Getting the results of your genetic mutation test

Getting the results of your genetic tests could take a few weeks. Ask your doctor how long they expect them to take. Contact your doctor if you haven’t heard anything after this time.

Waiting for test results or for further tests can be very worrying. You might have contact details for a lung cancer specialist nurse and you can contact them for information if you need to. It may help to talk to a close friend or relative about how you feel.

For support and information, you can also contact the Cancer Research UK nurses on freephone 0808 800 4040. The lines are open from 9am to 5pm, from Monday to Friday.
Last reviewed: 
08 Oct 2019
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