Though lung cancer continues to be the leading cause of cancer deaths in the U.S., huge advances in treatment have led to increased survival rates. Sometimes referred to as precision oncology, thanks to comprehensive biomarker testing, doctors can now treat each patient’s lung cancer individually. “We are not just treating lung cancer, we are treating YOUR lung cancer,” Dr. Eric Singhi, a thoracic medical oncologist in Houston, Texas and spokesperson for the American Lung Association said. “We are trying to get all the details about your tumor’s genetic makeup and once we get those details, we can truly tailor your treatment.” Biomarker testing is an essential step in the lung cancer diagnostic process that can help doctors determine if a patient has a biomarker and can be treated with certain targeted therapies with fewer side effects than traditional chemotherapy methods. But what exactly does it entail? Dr. Singhi explains.
Q: What is biomarker testing and who should get it?
A: All patients with non-small-cell lung cancer deserve and require biomarker testing. It is one of the most important steps in being able to try to personalize our lung cancer treatment for each patient.
For someone who doesn’t know, biomarker testing is a test that allows doctors to look at changes within the tumor cells themselves, specifically the DNA and RNA, trying to identify specific “drivers” that are causing the lung cells to grow rapidly into lung cancer. For example, EGFR, ALK, KRAS and other types of mutations. If we find one of these, we can treat the cancer, not just with traditional chemotherapy, but with targeted therapy that is very specific and personalized to your exact cancer.
There are two types of tests available to determine biomarkers. The first, a tissue biopsy test, requires obtaining some tissue from the primary lung tumor, if possible, or another disease site, and running tests on it. The second requires a non-invasive blood draw and testing the blood for the specific markers. Patients should feel empowered to ask about both options.
Q: What questions should patients ask their healthcare provider about biomarker testing?
First, patients should ask, “Has my tumor been tested for all the recommended biomarkers?” If it has, they should ask how it was done. Was it done with a tissue biopsy, a blood test or both? I think that's important.
Another question is, “Should I wait for results to come back before I start treatment?” Typically, the answer is yes, but if patients have symptoms or we need to more urgently get started on the treatment, then sometimes we go ahead and start with chemotherapy while we're waiting for those tests.
Then based on the results that they get from the biomarker testing, “Could my specific cancer be eligible for a clinical trial or targeted therapy?”
Q: What is targeted therapy?
Targeted therapy is a very specific, very precise type of cancer treatment. I describe it to patients as being like a lock and a key. Some lung cancers can have specific changes, or mutations, in their cells and those act-like special locks that help the cancer grow. Targeted therapy is designed specifically to fit into those locks and to block them, hopefully slowing cancer growth. This is very different from chemotherapy because chemotherapy non-selectively affects and tries to kill all types of fast-growing cells. So typically, targeted therapy will cause less side effects due it’s selectivity. Also, often we can offer patients this treatment as an oral pill as opposed to an infusion which is less disruptive to everyday life.
Q: How do you communicate the importance of biomarker testing to patients?
I think we all need to do a better job of slowing down and helping patients truly understand: 1.) that biomarker testing is incredibly important in lung cancer care, 2.) how it is performed, and 3.) what the timeline is for expecting the results. You may get it earlier, but it can sometimes take up to three weeks to get all of the results back. It is really important to get biomarker testing because it allows us to better understand the biology of the tumor so that we can try to personalize your treatment as much as possible.
Q: What are some common misconceptions about biomarker testing?
I think one of the misconceptions I hear a lot is that biomarker testing is only for patients who do not have a smoking history or for “non-smokers.” That's not true. Anyone with non-small cell lung cancer, regardless of a smoking history, should get biomarker testing.
A second misconception that I hear is that biomarker testing is only for patients with stage IV or metastatic disease. That is also not true. Patients, regardless of the stage of disease, even stage one, need to get biomarker testing because we do have FDA approved targeted therapy drugs for patients even with early stages of disease, and the only way to know if they qualify is to be tested.
Lastly, I often hear, “I already know I have lung cancer; we just need to treat it right away without waiting for the results for biomarker testing.” Sometimes starting treatment too quickly can create challenges. By waiting, we may have the chance to better personalize your care and choose a treatment that is more effective for you.
Q: What do you think can be done to get more patients tested?
I think it really starts with a system-wide policy trying to make biomarker testing automatic, not optional. That includes things like reflex testing for biomarker testing at diagnosis, trying to streamline insurance and approvals, and making sure that we educate providers. This includes not just providers at academic centers, but also those at community clinics which is where most of our patients with lung cancer are being treated.
When it comes to education, we can start by making sure it reaches people in many ways, across different settings, multiple platforms, and in different languages. Those are great first steps.
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Blog last updated: September 24, 2025
