In this study, we found that the CYFRA21-1 combined with the CEA was helpful in diagnosing LADC; the ProGRP and NSE were helpful in diagnosing SCLC; and the CYFRA21-1 was helpful in diagnosing LSCC, similar to the results of previous studies [33, 34]. This evidence concerns the gene CEACAM5 and small cell lung carcinoma.