Clinical And Analytical Performance Of Non-Small Cell Lung Cancer Biomarkers

A variety of biomarkers are currently used to help guide treatment decisions for patients with non-small cell lung cancer (NSCLC). These include mutation analysis for the EGFR and KRAS genes, along with gene rearrangement analysis for the ALK and ROS1 loci. In this study we have evaluated the clinical and analytical performance features of these assays in a series of formalin-fixed paraffin-embedded (FFPE) tissue samples. FFPE samples submitted for analysis of the EGFR, KRAS, ALK and ROS1 genes were evaluated using laboratory developed or FDA cleared assays. EGFR mutation analysis was performed using Sanger nucleic acid sequencing methods or the SNaPShot multiplex PCR, primer extension assay for exons 18-21. KRAS mutations were detected using allele specific PCR methods for codons 12 and 13, or pyrosequencing methods for codons 12, 13 and 61. Rearrangements involving the ALK gene were detected using the FDA-cleared break-apart FISH probes (Abbott Molecular). Genetic alterations involving the ROS1 gene were determined using FISH probes (Kreatech Diagnostics). Over 11,000 test results for these 4 markers are included in this analysis. Mutations in the EGFR gene were detected in 10.3% of samples evaluated (n = 8,701). A slightly higher percentage of samples from female patients (13%) had a detectable mutation compared to samples from males (7%) (chi-square p < 0.0001).