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Molecular and genetic testing for RLC cancers
Molecular and genetic testing help doctors find out if certain gene changes can guide treatment decisions and identify risks for inherited cancer.
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Overview
Every cell found in the human body has about 20,000 genes, which tell the cell what to do and when to grow and divide. Cancer starts because of changes to the genes (known as mutations).
Some people are born with a gene change that increases their risk of cancer (called an inherited faulty gene), but most gene changes that cause cancer happen during a person’s lifetime (called acquired gene changes).
For some people with an RLC cancer, doctors may recommend extra tests to look for acquired gene changes (molecular tests) or inherited gene changes (genetic tests). Ask your doctors whether you need to have molecular or genetic testing.
For some cancers, molecular or genetic tests may help make a diagnosis, or guide your doctor to the most effective treatment. For other cancers, these tests may not offer any benefit, or will not change what treatment is likely to be offered.
Molecular testing
You may be offered extra tests on a biopsy sample known as molecular or genomic testing. This looks for gene changes and other features in the cancer cells that may help your doctor decide which treatments to recommend.
Medicare may or may not cover molecular testing, depending on the cancer type. These tests can be expensive, so check the cost and how helpful they would be. If you are having molecular testing as part of a clinical trial, the costs may be covered.
Genetic testing
If your doctor suspects the RLC cancer is linked to an inherited or faulty gene (e.g. because other members of your family have had cancer), they may refer you to a family cancer clinic for more tests and genetic counselling.
These tests, known as genetic or germline tests, may help your doctor work out what treatment to recommend. The tests can also provide important information for your blood relatives, who may also have inherited a faulty gene.
Genetic counselling can help you understand what tests are available, and what results mean for you and your family. You may also want to be included on a hereditary or familial cancer registry in your state. If you feel worried or stressed, see Coping with a rare or less common cancer diagnosis.
Medicare covers some genetic tests, but others have a cost. Ask your treatment team what you will pay.
→ READ MORE: Treating RLC cancers
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Dr Damien Kee, Medical Oncologist, Austin Health and Peter MacCallum Cancer Centre, and Clinical Research Fellow, Walter and Eliza Hall Institute, VIC; Emeritus Professor Phyllis Butow, Psychologist, The University of Sydney, NSW; Alison Danis, Consumer; Dr Michelle Harrison, Medical Oncologist, Chris O’Brien Lifehouse, NSW; Jess Pike, Senior Social Worker, Westmead Hospital, NSW; Trish Taylor, Consumer; Lesley Woods, 13 11 20 Consultant, Cancer Council WA.
View the Cancer Council NSW editorial policy.