CTLA4 and head and neck squamous cell carcinoma: As shown in Figures 12A–C, the three subgroups shown the IPS is significantly higher in low risk group than that in high risk group, which indicated that the low-risk group might receive more benefits from anti-PD-1 therapy, anti-CTLA4 therapy or combined immunotherapy with anti-PD-1 and anti-CTLA4 than the high-risk HNSCC patients.