NOS2 and metastatic malignant neoplasm in the lymph nodes: The results showed that the positive area of macrophage marker (CD68) staining significantly increased in the lymph node metastasis group compared with the non-metastatic groups (p < 0.05), whereas the staining for M2 (CD163) and M1 markers (IL-1β and iNOS) showed no significant differences (P > 0.05; Figure 9A).