Biomarker Testing: Key to Personalized Lung Cancer Care

A practicing oncologist for more than 35 years, David P. Carbone, MD, PhD, directs the thoracic oncology center at The Ohio State University in Columbus. He is also a professor of internal medicine, coleader of the Translational Therapeutics Program, and president of the International Association for the Study of Lung Cancer, specializing in cancers of the chest, mostly lung cancer, mesothelioma, and thymoma. Here he discusses the importance of biomarker testing in both lung cancer overall and non–small cell lung cancer (NSCLC) specifically.

This transcript has been lightly edited for clarity.

Transcript

Can you discuss the importance of biomarker testing in lung cancer overall and specifically in NSCLC?

So the most common general type of lung cancer is non–small cell lung cancer, NSCLC, and biomarker testing has transformed the way we treat lung cancer from the days when we gave the same chemotherapy to everyone. Now, with biomarker testing, we have the ability to tailor the treatment to the patient and to the cancer in a way that results in highly effective therapies, often with very low toxicity. It's extremely important to do these sorts of tests before initiating any kind of therapy.

What biomarkers differ or overlap between early and late-stage lung cancers?

I suspect, as time goes on, the same biomarkers will be tested in both early- and late-stage disease. The only differences that we're seeing now are that the FDA approvals for drugs haven't kept up with the science in the early-stage disease like they've had an impact in advanced-stage disease right now. In the NCCN [National Comprehensive Cancer Network] guidelines, there are 8 or 9 different things that need to be tested for in non–small cell lung cancer in the advanced stage, but in the early stage, there's still relatively few approvals. I think in the early stage, the most important biomarkers are PD-L1, EGFR, and most recently, the approval for adjuvant alectinib for ALK fusion–positive resected lung cancer patients.

How are these test results interpreted across different stages of lung cancer?

Well, they are used to select the appropriate therapies. For example, a patient with a high PD-L1, you would select an immunotherapy, and in a patient with ALK fusion–positive disease, you would select an ALK tyrosine kinase inhibitor. These are completely different therapies, and the expected outcomes from those treatments are dramatically different in those 2 different populations of patients. So as I said, it's important to do this testing, and most often now, testing is done by in a panel that tests for all of these things at the same time. And as you might expect, patients with newly diagnosed lung cancer of any stage are anxious to get treatment underway. So I think the panel testing is the way to go in both early- and late-stage disease.

How expansive are biomarker panels?

The biomarkers are fairly well specified and described in the NCCN guidelines. But there are many companies that do this testing, and they each have a slightly different test platform and different numbers of genes tested for, and the technology between the testing is different—DNA and RNA and other sorts of testing. Some institutions do their own testing. At Ohio State, we have an in-house panel that is quite effective at finding these abnormalities. So, there are vast differences between different tests, but in a well-performed test, the results should be the same no matter how you test for them. The issue is often that it takes some time. Our tests come back in 10 to 14 days. Other times it can even take 3 weeks or more.