A cell-free DNA (cfDNA) test, or “liquid biopsy,” identifies more biomarkers and does so more quickly than tissue-based genotyping for guiding treatment in newly diagnosed advanced non–small cell lung cancer (NSCLC), according to a finding from a prospective study.
In 282 patients with newly diagnosed advanced NSCLC who were enrolled in the multicenter Noninvasive versus Invasive Lung Evaluation (NILE) study between July 2016 and April 2018, the “well-validated, comprehensive, and highly sensitive test” – Guardant360 – detected at least one guideline-recommended biomarker mutation in significantly more cases than did tissue-based tests alone (77 vs. 60 patients), Vassiliki A. Papadimitrakopoulou, MD, reported during a press conference highlighting data to be presented at the upcoming American Association for Cancer Research annual meeting in Atlanta.
“Additionally, the cfDNA results were delivered significantly faster than the standard-of-care tissue results [median, 9 vs. 15 days],” said Dr. Papadimitrakopoulou, chief of the section of thoracic medical oncology and the Jay and Lori Eisenberg Distinguished Professor in the department of thoracic/head and neck medical oncology at the University of Texas MD Anderson Cancer Center, Houston.
Guardant360 assesses for all guideline-recommended genomic biomarkers, Dr. Papadimitrakopoulou said, noting that nine such biomarkers have been identified. All biomarkers identified using the liquid biopsy were also detected in tissue every time.
“Plasma cfDNA testing therefore had 100% positive predictive value,” she said.
This is important, because “we know that about 30% of patients with newly diagnosed advanced non–small lung cancer have therapeutically targetable genomic alterations that make them eligible for targeted therapies,” she said.
“Identifying these patients is important, as the response rate to the properly identified targeted therapy is higher than response rates to first-line chemotherapy or immune checkpoint inhibitor therapy,” she added, explaining that tissue-based assessment has long been the standard of care option for identifying genomic biomarkers, but is limited by the risks associated with the biopsy procedure, the inability to test for all relevant mutations, and the time it takes – up to 30 days – to obtain results.
“[The NILE] results have very exciting implications for clinical practice, especially in light of the expanding list of genomic biomarkers to be assessed,” she said, concluding that the findings from NILE – the largest study of newly diagnosed advanced NSCLC – demonstrate that the clinical utility of this well-validated, comprehensive, sensitive cfDNA test “is cardinal in identification of patients with guideline-recommended biomarker-positive tumors, and it is an alternative to SOC [standard of care] tissue testing in the first-line testing.”
Clinical follow-up of patients is ongoing, she noted.
This study was funded by Guardant Health. Dr. Papadimitrakopoulou serves on the advisory boards of several pharmaceutical companies. She reported receiving CME speaker fees from F. Hoffmann–La Roche, and has received research support from Eli Lilly, Novartis, Merck, AstraZeneca, F. Hoffmann–La Roche, Nektar Therapeutics, Janssen, Bristol-Myers Squibb, Checkmate, Incyte and Guardant Health.
SOURCE: Papadimitrakopoulou VA et al. AACR 2019, Abstract 4460..