Clinical utility of a plasma-based comprehensive genomic profiling test in patients with non-small cell lung cancer in Korea

Objectives: Plasma-based comprehensive circulating cell-free DNA (cfDNA) next generation sequencing (NGS) has shown utility in advanced non-small cell lung cancer (aNSCLC). The aim of this study was to determine the feasibility of cfDNA-based NGS to identify actionable gene alterations in patients with aNSCLC.

Patients and methods: This single-center non-interventional retrospective study evaluated Korean patients with biopsy-confirmed stage III/IV non-squamous aNSCLC. Tissue biopsy samples were collected at baseline, and/or at progression and analysed with Standard of Care (SOC) testing; cfDNA was analyzed by NGS in some patients concurrently.

Results: aNSCLC patients with cfDNA test results (n = 405) were categorized into three groups: treatment naïve (n = 182), progressive aNSCLC after chemotherapy and/or immunotherapy (n = 157), and progressive aNSCLC after tyrosine kinase inhibitors (TKIs) (n = 66). Clinically informative driver mutations were identified for 63.5% of patients which were classified as OncoKB Tiers 1 (44.2%), 2 (3.4%), tier 3 (18.9%), and 4 (33.5%). Concordance between cfDNA NGS and tissue SOC methods for concurrently collected tissue samples (n = 221) with common EGFR mutations or ALK/ROS1 fusions was 96.9%. cfDNA analysis identified tumor genomic alterations in 13 patients that were unidentified with tissue testing, enabling initiation of targeted treatment.

Conclusions: In clinical practice, results of cfDNA NGS are highly concordant with those of tissue SOC testing in aNSCLC patients. Plasma analysis identified actionable alterations that were missed or not evaluated by tissue testing, enabling the initiation of targeted therapy. Results from this study add to the body of evidence in the support routine use of cfDNA NGS for patients with aNSCLC.