As shown in Table 2, its expression levels in gastric cancer tissues were significantly related to tumor stage (P = 0.037), distal metastasis (P = 0.048), tissue carcinoembryonic antigen (CEA) (P = 0.001), and carbohydrate antigen 19‐9 (CA19‐9) expression (P = 0.021). The gene discussed is CEACAM5; the disease is gastric cancer.