External validation of a panel of plasma microRNA biomarkers for lung cancer

Aim: We externally validate plasma miRNAs biomarkers for lung cancer in a large and retrospective sample set collected from a geographically distant population. Methods: Plasma samples are tested blindly to the clinical annotations by using PCR for quantitation of the four miRNAs in cohort 1 consisting of 232 lung cancer cases and 243 controls and cohort 2 comprising 239 cases and 246 controls. Results: Combined use of the four plasma miRNAs has 91% sensitivity and 95% specificity for diagnosis of lung cancer, and 85% sensitivity for early-stage lung cancer, while maintaining a specificity of 95%. Conclusion: The diagnostic values of the biomarkers are reproducibly confirmed in the independent and large sample sets, providing an assay for lung cancer detection.