AACR 2019: Clinical Utility of Cell-Free DNA Liquid Biopsy in Metastatic Lung Cancer
Posted: Thursday, March 14, 2019
Findings presented during a media preview of the upcoming 2019 American Association for Cancer Research (AACR) Annual Meeting (Abstract 4460) in Atlanta added to growing evidence that cell-free DNA testing detects Guideline-7 (G7) biomarkers at a rate similar to that of tissue genotyping tests for patients with metastatic non–small cell lung cancer (NSCLC). According to Vassiliki A. Papadimitrakopoulou, MD, of the MD Anderson Cancer Center, Houston, and colleagues, cell-free DNA testing can assess and identity biomarkers quicker than tissue testing and may rescue positive patients with nondiagnostic tissue results.
“The results of this study are exciting and reveal several important things,” said John D. Carpten, PhD, Program Chair of the AACR Annual Meeting, during the media previe. “Noninvasive approaches are feasible, and they meet standards that are minimally at the level of, if not superior to, more invasive approaches to disease detection.”
The prospective study enrolled 282 patients with previously untreated nonsquamous metastatic NSCLC undergoing standard-of-care tissue genotyping. Patients submitted a pretreatment blood sample for cell-free DNA testing.
Tissue testing identified a G7 biomarker in 60 patients, and cell-free DNA testing identified biomarkers in 77 patients. Among the 60 tissue-positive patients, cell-free DNA testing increased the number of patients with an identified biomarker by 48%. Of the 193 patients without a biomarker detected by tissue or cell-free DNA testing, 24 (12.4%) had an activating KRAS alteration identified in tissue alone or concordant with cell-free DNA.
Additionally, cell-free DNA testing had a significantly quicker turnaround time from test order to final results than tissue testing (9 days vs. 15 days, respectively).
Disclosure: The study authors’ disclosure information may be found at abstractsonline.com.