CEACAM5 and hemoglobin measurement: Furthermore, the results also revealed that age (p < 0.001), primary tumor location (p < 0.001), primary tumor size (p < 0.001), CEA (p = 0.014), T stage (p = 0.009) and N stage (p = 0.006) were obviously associated with OS (Table 2, Fig. 2), but CA199 (p = 0.143), HB (p = 0.206), mucinous adenocarcinoma (p = 0.740) and signet ring cell carcinoma (p = 0.164) had statistically insignificant associations (Table 2).