Lung cancer is the second most common form of cancer in the United States. Up to 85% of cases are non-small-cell lung cancer (NSCLC). Doctors usually diagnose NSCLC in adults over the age of 45, with the average age of diagnosis being 70.
As part of your lung cancer diagnosis, doctors take a biopsy to get more information about your tumor. The same tissue samples that led to a diagnosis of NSCLC can also be used to provide important information about your tumor that could help with treatment.
Here are seven common questions about biomarker testing in NSCLC.
What Is Biomarker Testing?
Even though 84% of annual lung cancer diagnoses are NSCLC, not all cancer cells are alike. Biomarker testing, also known as molecular or genomic testing, provides specific information about your tumor.
Your oncologist will look at cancer biomarkers such as:
- Proteins
- Gene mutations
- Extra copies of genes
- Missing genes
- Gene rearrangements
- Other substances
Comprehensive biomarker testing looks for the largest number of biomarkers that are linked to NSCLC. These are the specific biomarkers your doctor should test for in NSCLC:
- Anaplastic lymphoma kinase (ALK) gene rearrangement
- BRAF V600E mutation
- Epidermal growth factor receptor (EGFR) mutations
- KRAS mutation
- HER2 mutation
- MET mutation
- NTRK gene rearrangement
- PD-L1, PD1, TMB
- RET alteration (fusion)
- ROS1 gene rearrangement
- STK11 protein
Information from these biomarkers helps oncologists learn how cancer cells grow and what could make them die.
Who Needs Biomarker Testing?
Although not all lung cancers have biomarkers that benefit from targeted treatment, anyone diagnosed with NSCLC should undergo biomarker testing. ALK, EGFR, and other biomarkers are most common in those who have the adenocarcinoma subtype of NSCLC.
Can Biomarker Testing Help With NSCLC and KRAS Mutations?
The KRAS mutation is a protein error in normal cells. KRAS provides information to cells about growth. A mutation leads to cell overgrowth, causing cancer. There are multiple types of KRAS mutations, including the KRAS G12C mutation.
If biomarker testing shows you have NSCLC and a KRAS mutation, the standard treatment options include surgery, radiation, chemotherapy, and immunotherapy. There’s also a new targeted therapy called a KRAS inhibitor, which is a pill for those with the KRAS G12C mutation.
When Is the Best Time for Biomarker Testing?
Talk to your doctor about biomarker testing before you have a biopsy. Having the conversation early means your doctor will collect enough tissue from the biopsy to do comprehensive biomarker testing, which could help you avoid a second biopsy.
How Is Biomarker Testing Done?
The tissue from your tumor is sent to testing facilities at hospitals, medical centers, or universities where pathologists will look at it under a microscope to see what types of cells are in the tumor. Some biomarker tests might also use samples of blood or saliva to look at differences between your healthy cells and cancer cells.
Liquid biopsies are the latest biomarker testing option. The FDA approved liquid biopsies for lung cancer in 2020. The tests can identify biomarkers like EGFR in the blood. But you may still need tissue biopsies to look for specific biomarkers.
It takes an average of 1 to 2 weeks to get the results from comprehensive biomarker testing.
How Does Biomarker Testing Help With NSCLC Treatment?
There are several different treatment options for NSCLC, including chemotherapy, radiation, targeted drug therapy, and radiofrequency ablation. Different cancer medicines are designed to attack cancer cells with specific protein or gene changes, which means that not all cancer medicines work equally well on all cancer cells.
The most effective cancer treatments are tailored to the specific genes, proteins, and other substances that cause cancer cells to grow. This is the main reason why biomarker testing is often done before treatment for NSCLC starts.
Biomarker testing will help your oncologist decide which treatment has the highest chance of shrinking your tumor or slowing its growth. This is called targeted treatment.
The results from biomarker testing can provide important information about whether those targeted treatments are working. Biomarker testing results can also help guide you to some clinical trials. Here, researchers may be studying specific biomarkers, potentially giving you access to groundbreaking treatment options.
Over the past 10 years, targeted treatments have helped improve outcomes in those with NSCLC.
Does Insurance Cover Biomarker Testing for NSCLC?
Most insurance plans cover biomarker testing for those with NSCLC. Talk to your doctor, nurse navigator, or financial support team about insurance coverage and potential out-of-pocket costs for biomarker testing.
The more you know about biomarker testing for NSCLC and the KRAS mutation, the more prepared you’ll be to ask questions about your lung cancer diagnosis and treatment plan.
Show Sources
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SOURCES:
American Cancer Society: “Key Statistics for Lung Cancer.”
Lung Cancer Research Foundation: “Comprehensive Biomarker Testing for Lung Cancer.”
JAMA Oncology: “Update of Incidence, Prevalence, Survival, and Initial Treatment in Patients With Non–Small Cell Lung Cancer in the US.”
American Lung Association: “Biomarker Testing.”
Journal of the National Comprehensive Cancer Network: “What, When, and How of Biomarker Testing in Non-Small Cell Lung Cancer.”
American Lung Association: “KRAS and Lung Cancer.”
Lung Cancer Foundation of America: “Biomarkers and Why Testing is Important.”
Current Oncology: “Consensus Recommendations to Optimize Testing for New Targetable Alterations in Non-Small Cell Lung Cancer.”
