CCR7 and head and neck squamous cell carcinoma: Meanwhile, spearman correlation analysis illustrated a strong correlation between CCR7 and two essential M2 macrophage biomarkers, CD163 and MRC1 (CD206), in HNSCC patients (Fig. 1G; CD163 Spearman correlation coefficient = 0.457, P = 9e−27; CD206 Spearman correlation coefficient = 0.346, P = 2.95e−15).