If you or a loved one is diagnosed with lung cancer, understanding a few key letters — like EGFR, ALK, ROS1, and BRAF — can make all the difference in treatment.
Albert Rizzo, M.D.
Chief Medical Officer, American Lung Association
These letters represent gene mutations, or biomarkers, that play a critical role in how lung cancer grows and spreads. Biomarker testing can help you receive the most effective initial lung cancer treatment, which can lead to better health outcomes and fewer treatment side effects.
What are biomarkers?
Biomarkers are clues that physicians look for in tumor tissue and blood to help understand why lung cancer is growing and the best way to treat it. Lung cancer biomarkers can be errors in a cell’s DNA or high levels of proteins that live on cells. Treatments are available that specifically target and address many biomarkers, which is why it is important for people to know the results of biomarker testing before beginning lung cancer treatment.
It is important to know that there are types and subtypes of lung cancer, and within those subtypes, each person’s cancer can behave differently. Currently, biomarkers with approved targeted treatments are most common in patients with a subtype of non-small cell lung cancer (NSCLC) called adenocarcinoma. For example, mutations in the EGFR (epidermal growth factor receptor) gene are common in NSCLC. If a tumor tests positive for this mutation, then targeted therapies designed to block EGFR may be available as part of treatment to slow down or stop cancer growth. Similarly, mutations in genes like ROS1, BRAF, and ALK also have approved treatments tailored to them. Many other gene mutations are being studied with treatments in various stages of clinical trials before becoming available.
Targeted therapy drugs work differently than chemotherapy in that chemotherapy sends medicine throughout the entire body to kill many cells, including healthy cells, which may cause certain side effects like hair loss and digestive upset. Targeted therapies sometimes cause fewer side effects because they target exactly what is wrong with the cancer cells instead of killing normal, healthy cells, too. This can lead to a better quality of life and improve lung cancer treatment outcomes.
Unfortunately, not everyone with lung cancer will have biomarkers that can be treated with targeted therapies, but a discussion with your treating physician as to your particular cancer is worthwhile.
How to get tested
Biomarker testing typically requires a tissue sample from your tumor, which can be obtained through a biopsy. In some cases, a blood sample may be used for a liquid biopsy, which can detect tumor DNA in your bloodstream. Once the sample is analyzed, your doctor will have a clearer picture of what’s driving your cancer and can tailor your treatment plan accordingly.
If you’ve been diagnosed with lung cancer, ask your doctor about biomarker testing. It could open the door to more effective treatments that are better suited to your specific type of cancer.
Knowing your letters — like EGFR, ALK, ROS1, and BRAF — can help you beat lung cancer and give you a better shot at managing it effectively. Learn more at lung.org/biomarker-testing.
