CTLA4 and head and neck squamous cell carcinoma: Survival outcomes in patients with PD-L1 > = 20 in our cohort also compare unfavourably with the recent results from the experimental arms in the CheckMate-651 and KESTREL trials that assessed the efficacy and safety of either anti-PD1 or anti-PD1 plus anti-CTLA4 combination immunotherapy in R/M HNSCC; however, similarly to the KEYNOTE-048 trial, neither of those trials enrolled patients with ECOG PS 2.