CXCR4 and metastatic malignant neoplasm in the lymph nodes: Our data show that the incidence of lymph node metastasis is significantly higher (74%) in patients with tumors highly expressing both HIF-1α and CXCR4 than in those patients (43%) with tumors highly expressing only one of the molecules, or in those patients (11%) with tumors not expressing either of these two molecules.