The results showed that the AUC of serum CEA, CYFRA21-1, SCCA, CA125 and CA199 were 0.9217, 0.8680, 0.8888, 0.9994, 0.9975, respectively, and the 95% confidence intervals were 0.8716–0.9718, 0.8007–0.9353, 0.8222–0.9552, 0.9975-1, and 0.9926-1, suggestingthat serum tumor markers have diagnostic value for elderly NSCLC patients (Figure 4A-B). The gene discussed is CEACAM5; the disease is non-small cell lung carcinoma.