The serum levels of S100A11 and MMP-9 in patients with late-stage (stage III-IV) EOC were higher than those of patients in the early stage (stage I-II); the expression levels of S100A11 and MMP-9 in the serum of patients with lymph node metastasis were higher than the serum levels of patients without metastasis; the expression level of S100A11 and MMP-9 in the serum was high in patients with a large volume of ascites or large residual tumor foci. Here, S100A11 is linked to metastatic malignant neoplasm in the lymph nodes.