CD163 and metastatic malignant neoplasm in the lymph nodes: In the LSCC samples with lymph node metastasis, the mean density of CD163+ M2 macrophage infiltration was 124.2 ± 52.7 per 200 fields, whereas in the LSCC samples without lymph node metastasis, the mean density of CD163+ M2 macrophage infiltration was 103.3 ± 28.1 per 200 fields.