A Commentary on High PD-L1 Expression in NSCLC
Lauren Welch, MSN, NP-C, AOCNP, describes how she approaches management of patients with NSCLC and known high PD-L1 expression while she waits for pending biomarker testing results.
Joel Neal, MD, PhD: One of the other tests that's often highlighted, and we find that early on in immunohistochemistry tests part of non-small cell lung cancer, is PD-L1. Lauren, I was wondering if you see patients early on in the diagnosis and have been involved in the care of patients who have a diagnosis of non-small cell lung cancer, a very high PD-L1, but none of the molecular data back; and there's this eagerness to act on that?
Lauren Welch, MSN, NP-C, AOCNP: Absolutely, I feel like this happens almost every week. We've focused so much on trying to get the patient into clinic as quickly as possible that sometimes by the time that they're seeing us for their initial medical oncology evaluation we don't have all the results back. The patient's so eager – or anxious may be a better word – to describe how many of them are feeling, to know more about their cancer, to know more about the treatment. It can be a really challenging conversation to have to say, actually, we need to pause, put the brakes on until we get the rest of your testing back. A lot of what I do is making sure that all the testing has actually been ordered. That in between from biopsy to initial evaluation, PD-L1 is often reflexively performed and then I find depending on who's done the biopsy or where the patient may have had their initial biopsy done, sometimes limited panels are still ordered or there isn't always routine reflexing to next generation sequencing. That's always a difficult and lengthy conversation that we have to have with the patient.
Joel Neal, MD, PhD: Absolutely. I do want to make the point that PD-L1 is different. It's a protein marker on the outside of tumor cells and depending on where we sample the cancer and what point in time and what prior treatments there have been, PD-L1 is a lot more variable. Most of the other molecular diagnostic markers we talk about are root biomarkers. They really happen in the trunk of the branch of cancer tumorigenesis and as such they're in almost every single tumor cell probably as well as a host of other mutations that we don't talk about that may sometimes contribute to tumorigenesis or the incidental that we find.
