Dr. Isabel Preeshagul, a lung cancer specialist, provides insight about lung cancer subtypes and how test results may play a role in determining the best treatment option for patients.
Dr. Isabel Preeshagul is a thoracic medical oncologist at Memorial Sloan Kettering Cancer Center. Learn more about Dr. Preeshagul here.
When it comes to lung cancer, Dr. Preeshagul, what important tests should patients undergo that help in making treatment decisions?
So, it’s important to obviously confirm the diagnosis and make sure that it’s lung cancer, first of all. After that, you need to know the histologic subtypes. So, I mean, is this non-small cell, or is it small cell lung cancer?
And the difference between those two, it’s very important. They are not the same. Their treatments are different. Their prognosis is different. The staging is different. Everything is different. If you have non-small cell lung cancer, it’s important to know if you have adenocarcinoma or squamous cell carcinoma, large cell, neuroendocrine. It’s really important because the treatments vary. The prognosis varies. And how we approach those patients is different.
In addition to that, over the past 10 years, we have really come to understand the importance of next-generation sequencing testing, which I know we’re going to get to. But evaluating to see if your patient harbors any mutations or alterations that could be targetable because that would really change your treatment plan.
All right. So, let’s get to some of that testing. What is biomarker or molecular testing?
Sure. So, we use a lot of these terms synonymously. So, alteration, mutation, positive biomarkers, these are all basically one and the same. So, if you look at lung cancer 20 years ago, we really didn’t know about any of these. You had lung cancer, you got X, Y, and Z chemo. And that really was it.
But with the discovery of EGFR alterations and realizing that some patients harbor an EGFR mutation, and this mutation is what’s driving their tumor and then the discovery of erlotinib, or Tarceva, we realized that it’s important to evaluate for the presence of these mutations.
So, these are somatic mutations that occur within your tumor and drive your tumor to grow, and some of these alterations are targetable.
But some of these alterations that we find, unfortunately, and the majority of them, we don’t really know the significance of them as of yet, or we know the significance of them, but we don’t have a magic bean to treat them. But that does not mean that there won’t be something in the future.