CCR7 and head and neck squamous cell carcinoma: Whereas naïve T cells (CD45RA+/CCR7+) constituted 33.2 ± 18.3% of T cells in the peripheral blood of healthy controls, their percentage in PBMC HNSCC was 22.4 ± 14.6%, in tumor samples 4.1 ± 3.8% and in non-cancerous mucosa 7.7 ± 7.2% (Figure 1D, left plot).