The objective of this study was to evaluate prospectively manner the prognostic significance of clinical-pathological factors, serum CEA levels, and EGFR and HER2 lung expression in brain metastasis development and OS in patients with recent diagnosis of advanced NSCLC (clinical stage IIIB-IV) treated with platin-based cytotoxic chemotherapy or EGFR inhibitors. This evidence concerns the gene CEACAM5 and non-small cell lung carcinoma.