The main findings of this study were: (1) tumor markers including CEA, CA19-9, and CA50 were independent prognostic factors for T4a stage gastric cancer; and (2) there were significant differences of overall 5-year survival rate between CEA (+) and CEA (-) according to stages II and III; between CA19-9 (+) and CA19-9 (-) according to stage III; between CA50 (+) and CA50 (-) according to stage III. This evidence concerns the gene CEACAM5 and neoplasm.