Precision Medicine Has Broadened the Application of Gene Therapy Testing, Further Specialization May Be Needed to Interpret Results

Following the advent of precision medicine, the oncology field shifted dramatically over the next 10 years, explained John Marshall, MD, Clinical Director of Oncology for Georgetown University, during a panel discussion at the 2023 NCODA Oncology Institute. Ten years ago, immunotherapies were thought of as ridiculous, and were placed in the back alley of ASCO in the 400 section.

“Now, [immunotherapy research] is in the poster discussion section, and you need a tractor pull room to just talk about the latest postings,” Marshall said. “[Further], 10 years ago, gene therapy testing was quite unusual. You had to know [estrogen receptor/progesterone receptor (ER/PR) tests] for breast cancer, and a few others here and there. But for the most part, we didn't do it.”

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Now, Marshall explained that essentially every patient with the least advanced disease needs some form of gene therapy testing. Also, 10 years ago, oncologists would comment to each that cancer treatment could not get more expensive than it was at that time.

“Now look where we are [with drug pricing],” Marshall said. “Also, 10 years ago, [those in] oncology were the happiest with the highest quality of life of all medical subspecialties. Now, we have the highest suicide rate among all medical subspecialties. So, it is not easy what's going on in the trenches.”

Marshall noted that, to a significant degree, the problems occurring for oncology professionals have to do with the complexity of what's going on in the field. Ten years ago, it was possible to know close to everything in terms of the options for treatment opportunities and selection.

“We didn't need a computer to look [therapies] up on the spot. Nowadays, we have to look stuff up,” Marshall said. “Today, we can agree that all cancer patients should be profiled, and the technology [for this] is just through the roof fast. The tests we ordered a couple of years ago are different today; we have different tests. But it falls on us to prove that there's value in all of this.”

During the panel discussion, Jerry Mitchell, MD, MBA, Director Field Medical Oncology at Foundation Medicine, noted that when he came out of a fellowship to treat lung cancer, he needed to know a patient’s performance status and details about a limited number of therapies.

“And that was it,” Mitchell said. “Today, I've got to know the nuances of the testing, I've got to know the differences, and I've got to know the genes. And that is just not something that we can do as individual providers—we have to work as a team. No single provider can treat precision medicine the way it needs to be treated. Now, it’s a team model, and I think that's an essential message.”

Marshall added that as physicians, they also need support when reading the results of certain gene tests, as the field is advancing quickly without the same systems in place that have been established in radiology to help physicians interpret test results.

“If I order a CAT scan, I can actually get that CAT scan and do a pretty decent job of reading it,” Marshall said. “I can tell the quality of the scan, whether there's been contrast, etc. I get back a gene test from some company that I sent it out to, or even in my own internal lab, and I have no sense of the quality of that.”

Marshall explained further that those instincts regarding therapeutic decision-making based on gene test results just aren't there. Mitchell agreed, adding that gene tests can also vary from lab to lab.

“And you don't really know what's under the hood,” Mitchell said. “Trying to figure out what's the best one versus another test and what's quality? That's your technicians. And in genes, not only are they obscure, but they're changing every day.”

Jonas Congelli, RPh, Chief of Pharmacy, Laboratory, and Nutrition Services at the Hematology Oncology Associates of Central New York, noted that an additional specialization in an area such as molecular pathology could help train professionals to interpret gene test results and include those details in the results sent back to physicians from the lab.

“The other challenge, too, is the naming convention can differ depending on who's doing the test. For example, MET exon 14 skipping mutation—in the Foundation Medicine tests, they call it ‘MET exon 14 splice site mutation.’ So even our naming convention or nomenclature is inconsistent across the platform,” Congelli said. “This just leads to additional confusion as to what it is that I'm looking at. So, I think there's going to be some ongoing specialization that's going to occur.”

Congelli explained that his practice had implemented molecular tumor boards, but sometimes it was being run in a more retrospective fashion as an educational tool rather than a focused effort toward an immediate treatment decision. To change this, Marshall noted that a specialist is needed to interpret test results in real-time.

“When I open one of these, I really feel like I am Charlie opening a chocolate bar, wondering if there's a golden ticket inside,” Marshall said. “I really want to know ‘Is this going to be something that transforms this patient's outcome?’ Most of the time, I get a RAS mutation, which is sort of like, ‘I got a rock.’”

Mitchell noted that to effectively implement strategies to advance the implementation of precision medicine, it is necessary to look in a systematic way at where the implementation process may be obstructed.

“At the end of the day, we've got information that's in the DNA, and we want to get that information to the physician so that they can ultimately get a therapy that works for the patient,” Mitchell said. “It's that whole value stream.”

Reference

Congelli J, Marshall J, Mitchell J. Understanding Precision Medicine and the Role of the Industry Partner with Medically Integrated Teams. Presented in Minneapolis, Minnesota at NCODA Oncology Institute; Aug 16, 2023.