Precision Medicine: A Collaborative and Multidisciplinary Approach to Identifying Biomarkers - Episode 7
Expert pathologist Samuel K. Caughron, MD, FCAP, shares best strategies for the timing and utilization of biomarker testing while managing patients with cancer.
Transcript:
Samuel K. Caughron, MD, FCAP: So, comprehensive genomic profiling in solid tumors is the standard of care in several tumor types in most, if not all, advanced solid tumors today. When you think about what we're able to do with comprehensive genomic profiling, I actually compare it to what happened when the first surgeons looked through the early microscopes and could see the individual cells interacting and identified and began to understand what cancer was.
With comprehensive genomic profiling, we go that next level deeper into biology. We're now seeing not only the cells, but also into their biology. What is the interaction? What are the mutations within the DNA? What is the RNA? What's the RNA look like in these tumors? How is that driving the tumor? So, it's sort of almost a philosophical level with comprehensive genomic profiling, and we can have an understanding of tumors and solid tumors like we've never had before.
If you took cost out of the equation [with] comprehensive genomic profiling, there'd be almost no reason not to do it on every tumor to better understand the disease. That's the disease process. So, practically today, at what point do I recommend performing molecular testing? Well, I think it should be done any time there's not a clear path to an effective treatment for that patient and to better understand what other treatment options may be available. Again, that's going to most often be in an advanced disease setting or in some diseases that may be earlier, depending on what the disease is and what the treatment options are.
Whether or not to retest upon progression, or to answer that question at progression, the disease may be the same or it may have changed. And so, I think you must look at each individual patient. Though, going back to that theme of comprehensive genomic profiling, we're interrogating and better understanding the disease at its deepest level. Yes, retesting upon progression in patients where there's the belief that there may be hope for another treatment benefit, it should be done.
So, as molecular pathologists, our job is to oversee high-quality testing and to make sure those results are available to the treating physician, so that at the time they are making decisions about what therapies the patient will be put on, or perhaps whether the patient's going into hospice, they have that information available. Today, virtually every patient has an electronic health record and making sure the biomarker results and the genomic profile of the tumor is in the electronic medical record is a key part of ensuring that that information is available to the treating physician. It doesn't stop there. I think active verbal communication as well at tumor conferences, for example, is a key part of the communication, and the integration of results into the patient's chart.
So, again, as a molecular pathologist, I'm not directly treating patients. However, be aware that getting results back on the chart or back to the treating physician so they can have a conversation with the patient, and make treatment decisions, is important. Therefore, in the lab, we cannot become complacent about the urgency with these tests and to get those results back as quickly as possible. One of the things I caution pathologists and my laboratory colleagues about is becoming complacent about the turnaround time on these tests. We know it takes a while to get back, but we can't let the fact that these tests themselves do have an intrinsic time to get the results back be an issue. We can't let that delay make us complacent about the urgency to get these results back on the patient's chart. Patients who have metastatic non–small cell lung cancer have, I think, a median 16-week progression-free survival. They need to have these results so they can get on treatment.
The single greatest tool/resource that we have implemented within our program that has helped with biomarker testing was a resource for the pathologists based on a multidisciplinary meeting. It was to identify what biomarkers the pathologist will initiate testing for at the time of diagnosis. So, we put together a cheat sheet that the pathologist has, we distributed [it] to all our pathologists, and it has different common diagnostic tumor types or diagnosis categories. What biomarkers the multidisciplinary meeting identified as appropriate to initiate at the time of diagnosis. Using that, we've been able to get biomarker testing underway promptly. So, it helps shorten the turnaround time for the most common scenarios. For example, on small cell lung cancer, obviously breast cancer, but also colon cancer, pancreatic, and several other different cancer types. So, that's probably what we've had the most success with.
Transcript edited for clarity.