In multivariate analysis, preoperative carcinoembryonic antigen (<i>p</i> = 0.014), tumor size (<i>p</i> = 0.010), tumor location (left-side colon; <i>p</i> = 0.033; rectum; <i>p</i> < 0.001), and pT stage (T3, <i>p</i> = 0.009; T4, <i>p</i> < 0.001) were significant factors of eOB. This evidence concerns the gene CEACAM5 and neoplasm.