The short answer
Biomarker testing looks at the genes and proteins in a cancer to help choose treatments most likely to work. This approach, called precision medicine, can match people to targeted therapy or immunotherapy based on their tumor's specific features.
Biomarker testing examines the genes and proteins in a person's cancer.
It helps match people to treatments most likely to work for their specific tumor.
This approach is called precision medicine or personalized medicine.
Results can point to targeted therapy or immunotherapy options.
Choose how you want to understand this
The full explanation.
The simple version
Two cancers that look the same under a microscope can be driven by different genes. Biomarker testing looks at the genes and proteins in a person's cancer to help choose the treatments most likely to work. This is the idea behind precision medicine.
How it works
A sample of the cancer — from a biopsy or surgery — is tested for specific genes, proteins, or other markers. If a change is found that a drug can target, that treatment may be an option.
Biomarker testing matches the treatment to the specific features of your cancer.
What it can point to
Results can point toward targeted therapy (drugs aimed at a specific change in the cancer) or immunotherapy (treatment that helps the immune system). Matching treatment this way can make it more effective and sometimes less toxic.
Its limits
Not every cancer has a change that current drugs can target, so testing does not always change treatment. But it is increasingly a standard part of planning care, and the number of targetable markers keeps growing.
Words to know
Tap any term to see what it means.
Common questions
▸What is biomarker testing?
Biomarker testing looks at the genes, proteins, and other features of a person's cancer. Also called tumor or molecular testing, it helps doctors understand what is driving the cancer.
▸What is precision medicine?
Precision medicine means using information about a person's cancer — especially its biomarkers — to choose treatments most likely to help. It is also called personalized medicine.
▸How does it change treatment?
If testing finds a specific change, a targeted therapy or immunotherapy aimed at that change may be an option. This can make treatment more effective and sometimes less toxic than a one-size-fits-all approach.
▸Does every cancer have a biomarker to target?
No. Not every cancer has a change that current drugs can target. But testing is increasingly part of planning care, and options are growing.
Questions to ask your doctor
Being prepared helps you get the most out of your appointments. Save or print these questions.
Tap a question to save it to your list (kept on this device).
Test your knowledge
0 of 3 answered
This quiz checks understanding of educational content only. It is not medical advice. Open this quiz on its own page.