Nevertheless, due to the differences in clinical and biological characteristics, the survival of gastric cancer patients with the same stage is variable, which highlights the need to look into other significant prognostic factors, such as tumor markers, which may allow the assessment of the individual prognosis of patients [2,3]. In clinical practice, cancer antigen (CA) 19-9 and carcinoembryonic antigen (CEA) are the frequently used markers for the early diagnosis and monitoring of gastric cancer [4,5]. Here, CEACAM5 is linked to gastric cancer.