In terms of cellular immunity, we identified a significantly smaller number of total T cells in the NPC group than in the HC group (p = 0.0338, Figure 2A), which was attributable to the significantly smaller number of naïve CD4 and CD8 αβ T cells observed in the NPC group (p = 0.0048 [naïve CD4 αβ T cell] and 0.0048 [naïve CD8 αβ T], Figure 2B). Here, CD4 is linked to nasopharyngeal carcinoma.