The present study only evaluated the clinical significance of serum sTLR4 and HMGB1 in a relatively small group, so further studies are required to validate these results in large-scale and compare them with other existing biomarkers of NSCLC, such as squamous cell carcinoma antigen, cytokeratin 19 fragment 21–1, carcinoembryonic antigen, cancer antigen-125, or carbohydrate antibody 19-9 [33]. This evidence concerns the gene CEACAM5 and non-small cell lung carcinoma.