The most common utilization pattern of tumor markers before first discharge was combination of CEA, Cyfra21‐1, NSE, and SCC tests with the test frequency of 1174 (27%) in NSCLC (Appendix Figure S2A) and 233 (30%) for SCLC (Appendix Figure S2C). This evidence concerns the gene CEACAM5 and non-small cell lung carcinoma.