CEACAM5 and neoplasm: These factors, generally validated in univariate studies and with significant biases, were considered in the work published by Dehing-Oberije et al., who proposed a combination of clinical factors (the WHO health status classification (WHO-PS), forced expiratory volume in the first second (FEV1), gross tumor volume (GTV) equivalent to the size of the main tumor component, nodal load, and sex) with biomarkers obtained from peripheral blood (CEA and IL-6), thus obtaining an improvement in the prognostic capacity at two years of patients affected and treated for NSCLC [60].