CD8A and head and neck squamous cell carcinoma: As CD8+PD-1+TCF1+ Texprog and CD8+PD-1+TCF1− Texterm were detected in HNSCC, we investigated their prognostic value in the Sun Yan-Sen University (SYSU) cohort with 102 patients (patient clinicopathological information is presented in Table S2), based on the density of these two subsets in the mIHC results.