1. Understand the Terms
What is a biomarker?
A biomarker is a gene, protein, or other substance that is in your blood, bodily fluids, or cells. Biomarkers are also called tumor markers.
What is biomarker testing?
Biomarker testing is a way to look for those biomarkers that can provide information about your cancer. It can be confusing, because biomarker testing can be called different names, including:
- Genomic testing or profiling
- Tumor testing or subtyping
- Tumor genetic testing
- Somatic testing
- Companion diagnostic testing (when paired with a specific treatment)
Some biomarker tests can test a solid tumor, and some can test your blood and other fluids for biomarkers (i.e., liquid biopsies).
Why is biomarker testing useful?
Biomarkers may affect how certain cancer treatments will work and understanding your biomarkers can help you and your health care team make treatment decisions that are best for you. This is often called personalized or precision medicine. Biomarker testing is a key part of getting access to precision medicine. For example, some targeted therapies may only work if you have certain biomarkers.
Is biomarker testing different from genetic testing?
Genetic testing is not the same as biomarker testing. Genetic testing is a test to find out if you have an inherited genetic mutation. You inherit your genes, and sometimes genetic mutations, from your parents. You are born with those mutations. Genetic mutations may make it more likely that you will develop a specific type of cancer. For example, if you have the BRCA1 or BRCA2 mutations, you are more likely to get breast, ovarian, and other cancers.