Biomarker Testing of Patients With NSCLC Can Aid Survival

Comprehensive biomarker testing of patients with non-small lung cancer (NSCLC) is a critical part of their care and their survival, explains David M. Waterhouse, MD, MPH. Actionable biomarkers, he adds, are genetic modifications that initiate malignancy but that can be targeted by an FDA-approved treatment.

“If you conduct biomarker testing, about 45% to 50% of actionable biomarkers could change the course of treatment for patients with NSCLC,” Dr. Waterhouse says. “Both cost-effective and cost-efficient, biomarker-directed therapy is superior to standard of care. Most importantly, it has been shown to improve survival. There is a significant difference in survival between those patients who had biomarker testing and those who did not.” However, he adds, biomarker testing rates remain suboptimal.

Dr. Waterhouse cited the Molecularly Informed Lung Cancer Treatment in a Community Cancer Network: A Pragmatic Consortium (MYLUNG), a collaborative and innovative research study comprising three protocols over a 5-year period, which studied up to 12,000 patients with NSCLC in a community setting. Researchers conducted a retrospective study from 2018 to 2020 of 3,474 patients with metastatic NSCLC. They examined the use of full next-generation sequencing (NGS), time from diagnosis to first-line therapy, and biomarker turnaround rates. NGS, according to researchers, can detect multiple types of genomic alterations and has the ability to interpret the mechanism of pathogenesis and improve diagnostic and therapeutic testing. “NGS consists of multilevel tests, 20 tests that can reveal more than 450 biomarkers associated with the cancer process,” Dr. Waterhouse explains. “It’s both a prognostic and predictive tool.”

Biomarker Testing Rates for NSCLC Remain Suboptimal

Overall, 90% of patients in the MYLUNG Consortium had at least one biomarker tested. “NGS testing rates were poor (<50%), but increased from 33% to 44% during this period,” Dr. Waterman points out, adding that testing rates improved from December 2020 through September 2022 in 57% of patients in their follow-up prospective trial. Testing rates were lower among patients with early-stage lung cancer.

He agrees that testing is critical for both early-stage and advanced-stage NSCLC. “There are currently ten actionable biomarkers in advanced-stage testing, with a lower number of actionable biomarkers in testing for early-stage NSCLC,” he says. “But that doesn’t mean you don’t do the testing.”

While most healthcare professionals support biomarker testing for NSCLC, there’s a gap in the number of tests they perceive they are conducting versus how many tests are actually performed, Dr. Waterhouse adds. “It’s not that they object to testing patients, it’s that they face several barriers,” he says. “For one, the tests can be challenging. You need to have sufficient tissue to be tested and this is not always the case with biopsied tissue. The turnaround time is considered lengthy, from 10 to 14 days. And some physicians are not sure how to interpret the tests—not everyone has access to a molecular pathologist.”

A major barrier is that oncologists are simply overwhelmed, he says. “A doctor will spend between 15 and 20 minutes with each patient, which includes tending to patients’ questions and concerns about their cancer and the documentation that accompanies every visit. Biomarker testing can be tough to integrate into their practice.”

Dr. Waterhouse and colleagues, who published a study on closing the testing gap in JCO Oncology Practice, would like to see a 100% testing rate in patients with NSCLC. “Right now, nationally, we’re at around 60% to 65%,” Dr. Waterhouse says. “That’s nowhere near enough. We were, however, able to push that rate up to 93% in our study. Efforts to scale these processes are ongoing.”