Moreover, the diagnostic value of the combination of the four miRNAs plus CEA had an AUC of 0.861, with a sensitivity of 48.2% and a specificity of 82.6%, to distinguish NSCLC from pneumonia (P = 0.0031, 95% CI: 0.586–0.750; Fig 6 and S3 Table). The gene discussed is CEACAM5; the disease is pneumonia.