FOXP3 and neoplasm: In addition, multivariate analysis demonstrated that FoxP3+ Treg infiltration in the ST compartment (RFS, p = 0.05; OS, p = 0.015), tumor stage (RFS, p = 0.005; OS, p = 0.002) and tumor histological grade (RFS, p < 0.0001; OS, p = 0.031) are three significant prognostic factors for HNSCC that are strongly independent from each other.