Rapid Blood Tests for Lung Cancer Yield Clinically-Actionable Results

April 25, 2017
Bryant Furlow
Bryant Furlow

Circulating tumor DNA blood tests can rapidly identify treatment-targetable tumor mutations in patients diagnosed with non–small-cell lung cancer.

Circulating tumor DNA (ctDNA) blood tests can rapidly identify treatment-targetable tumor mutations in patients diagnosed with non–small-cell lung cancer (NSCLC).

The team also validated RNA-based mutation assays, but these had a higher failure rate (9.5%) than the DNA tests (< 1%), cautioned lead study author Hestia Mellert, PhD, of Biodesix, Inc., in Boulder Colorado, and coauthors.

“This study validates a blood-based genome testing service that provides accurate results within 72 hours,” the authors reported in TheJournal of Molecular Diagnostics. “This rapid, highly sensitive, and actionable blood-based assay service expands testing options and supports faster treatment decisions.”

The researchers validated clinical blood tests for targetable tumor gene variants in advanced NSCLC, such as KRAS variant G12C/D/V, epidermal growth factor receptor (EGFR) variant L858R, exon 19 deletion and T790M, using blood samples from 219 patients with cancer and 30 control participants without cancer diagnoses.

Clinical sensitivity for each gene variant in the panel ranged from 79% to 100% and specificities ranged from 94% to 100%, they reported. The team also processed 1,643 NSCLC clinical samples with the panel, yielding results within 72 hours for 94% of those tests.

The testing identified EGFR-sensitizing mutations in 10.5% of panels processed, 13.8% with EGFR-resistance mutations, 13% with KRAS mutations, and 2% EML4-ALK fusion mutations.

Only approximately 20% of patients diagnosed with cancer have tumor genomics available at their first cancer treatment consultation and up to 25% of patients receive genomic testing results only after treatment has begun, the study authors noted.