Across all nodal stages (N0 to N3), promoter methylation levels of CCL18 and EGF remained significantly lower in tumor samples compared to normal tissue (normal: 97; N0 = 230; N1 = 242; N2 = 97; N3 = 20; p < 0.05) (Figures S4A and S4D). Here, CCL18 is linked to neoplasm.