We evaluated the correlation between serum CEA, CA199, CA125, CA724 levels and pathological features in 572 patients with gastrointestinal tumors.The levels of serum CEA, CA199, CA125 and CA724 were compared between the two groups, and the area under the receiver operating characteristic (ROC) curve (AUC) was used to evaluate the diagnostic efficacy of these markers alone and in combination. Here, CEACAM5 is linked to digestive system neoplasm.