As illustrated in Table 1, serum CCL18 level was positively associated with primary tumor site (Glottic vs. Others; P < 0.001), tumor classification (T1+T2 vs. T3+T4; P < 0.001), clinical stage (I+II vs. III+IV; P < 0.001) and lymph node metastasis (N0 vs. N+; P < 0.001). The gene discussed is CCL18; the disease is metastatic malignant neoplasm in the lymph nodes.