Abstract
PURPOSE: The Blood First Assay Screening Trial (BFAST) is a prospective study using next-generation sequencing (NGS) of circulating tumor DNA (ctDNA) in treatment-naïve advanced/metastatic non-small-cell lung cancer (NSCLC). We compared liquid biopsy to tissue testing and analyzed genomic alterations in Taiwanese patients with NSCLC using the BFAST database. MATERIALS AND METHODS: A total of 269 patients underwent FoundationOne Liquid Companion Diagnostic (F1LCDx) assay at the National Taiwan University Hospital, of whom 264 underwent tissue-based genetic testing also. We analyzed the actionable mutations and the concordance between tissue-based genetic testing, which was limited to EGFR, ALK, ROS1, and BRAF, in a real-life clinical setting and blood-based NGS in the clinical trial. Additionally, we analyzed the co-occurring genomic alterations from the blood-based ctDNA assay. RESULTS: A total of 76.2% patients showed actionable mutations. Standard tissue testing did not detect known driver alterations in about 22.7% of the patients (sensitivity, 70.24%). Liquid NGS detected additional mutations (RET, KRAS, MET, and ErbB2) in 14% of the patients, which went undetected by the standard-of-care testing. The complementary use of ctDNA NGS increased the detection rate by 42%. The F1LCDx assay had a sensitivity of 83.41%. Lower tumor and metastasis stages predicted nondetected blood-based NGS ctDNA results. Common co-occurring mutations in the blood-based NGS ctDNA assay were TP53, DNMT3A, TET2, PIK3CA, CTNNB1, and RB1. Among the patients with EGFR-mutated NSCLC, TET2 co-occurring alterations correlated with shorter progression-free survival of EGFR tyrosine kinase inhibitor treatment. CONCLUSION: NGS ctDNA analysis in comprehensive genetic testing improves actionable mutation identification, vital for treating Asian NSCLC cases with high actionable mutation rates. Lower stages correlated with undetected blood-based NGS ctDNA assay results.