CEACAM5 and neoplasm: Although the tumor CEACAM5 promoter methylation percentage in the elevated sCEA level group did not show significant difference compared with the normal sCEA group (p = 0.478; Figure 3A), when excluding 24 patients who escaped from inactivation by DNA methylation (those with increased CEACAM5 promoter methylation and elevated sCEA), the increased sCEA expression group showed a significantly lower CEACAM5 promoter methylation percentage (p = 0.016; Figure 3B).