Beyond Early Stage: Biomarker Testing's Role in Advanced Lung Cancer

In part 1 of our interview with David P. Carbone, MD, PhD, director, Thoracic Oncology Center, The Ohio State University (OSU) in Columbus, he addressed why it is important to conduct biomarker testing in both lung cancer overall and non–small cell lung cancer more specifically. Here he continues the discussion on biomarker testing by explaining the cost breakdown and how even in late-stage disease, biomarker testing serves its purpose.

Carbone is also a professor of internal medicine and coleader of the Translational Therapeutics Program at OSU, and president of the International Association for the Study of Lung Cancer.

Transcript

What is the cost impact of biomarker testing in lung cancer on value-based care?

Health care is expensive, and these tests are not cheap. Usually they run a few thousand dollars. Some of the simpler tests can be less expensive, but the fact is, a single dose of some of these drugs is way more than that cost. A dose of [pembrolizumab] can be over $10,000. The fact is, these biomarker tests are so important in selecting therapy—and you only need to do this once at the time of diagnosis, in general. I mean, we do repeat testing in resistant disease, but this is not a test that you need to do every 3 weeks. This is a test you do at the beginning of therapy, and it makes such a huge difference in the way a patient is treated, in the selection of which treatment is appropriate, that it's incredibly cost-effective in my mind. It costs less than a PET scan or other things that we don't think about charging for. So this is, to me, an absolutely essential expense in appropriate management of lung cancer.

What purpose does biomarker testing serve in late-stage disease?

It’s very similar in early- and late-stage disease, in theory. If you have a patient with an ALK fusion abnormality in their tumor, that patient should be started on first-line alectinib or other drugs targeting ALK. And the same thing if you have an early-stage patient who gets a surgical resection and it's found to be ALK-fusion positive; that patient should receive alectinib as an adjuvant therapy. It's used to select therapies in exactly the same way, but in an advanced-stage patient, they usually start those therapies right away and in an early-stage patient, often surgery is followed by the targeted therapy.

We always try to have curative intent. But for immunotherapies, PD-L1–positive patients, especially have a chance of being effectively cured of their lung cancers, even in advanced stage, stage IV. There are many patients who are alive 5, 6, 7, 8 years later with no evidence of disease off therapy. So I do say that there is some chance of cure with immunotherapy. Overall, it's about 20% of people who are alive at 5 years—which doesn't sound great, but it's a whole lot better than decades ago, when almost no one survived even 2 or 3 years with advanced lung cancer.

With the targeted therapies, though, these right now are not thought to be curative, and eventually the cancer will become resistant and come back. But recent data, especially with ALK-fusion positive tumors, there are patients that are on therapy without recurrence for a decade, and that's that's very exciting. When you think about the average survival for metastatic lung cancer, it historically was 4 to 6 months from diagnosis to death. Now we're talking about 5 to 10 years. It's a huge improvement.

Not everybody benefits from these and not everybody has a biomarker match, but it's important to look. And if you miss a biomarker match that's there because you didn't test or you didn't interpret the test properly, that's a real tragedy for that patient where they could have been helped more effectively. But it is true that some patients have no targetable biomarkers and a PD-L1 of 0 and don't respond to anything. We need to work harder to find therapies for those people.