In the univariate Cox regression analysis, the PSGC, carcinoembryonic antigen (CEA) level, carbohydrate antigen (CA) 19-9 level, tumour location, tumour size, Lauren type, depth of invasion (T stage), lymph node metastasis (N stage) and distant metastasis (M stage) were significantly associated with OS in the training cohort (Table 2). Here, CEACAM5 is linked to metastatic malignant neoplasm in the lymph nodes.