Patients with lymph node metastasis exhibited increased promoter methylation frequency (χ2 = 5.239, P = 0.022) and low DKK2 mRNA expression (χ2 = 3.958, P = 0.047) compared with patients with no lymph node metastasis. Here, DKK2 is linked to metastatic malignant neoplasm in the lymph nodes.