Moreover, there have been studies trying to establish some readily available biomarkers, such as the lymphocyte-to-monocyte ratio (LMR), albumin-to-globulin ratio (AGR), platelet-to-lymphocyte ratio (PLR), neutrophile-to-lymphocyte ratio (NLR), and levels of cancer-specific markers, i.e., the carcinoembryonic antigen (CEA) and α-fetoprotein (AFP). This evidence concerns the gene CEACAM5 and cancer.