Therefore, they have been the important clinical means of auxiliary examination in the clinical diagnosis and prognosis evaluation for tumors.[5,6] Among the available tumor markers, carcino-embryonic antigen (CEA), carbohydrate antigen (CA) 19-9, and CA72-4 are widely used in the follow-up of patients with gastrointestinal malignancies. The gene discussed is CEACAM5; the disease is neoplasm.