CD274 and neoplasm: This data is interesting considering the fear of performing biopsies in previously irradiated areas and that up to 40% of patients do not have tumor biopsies suitable for histological PD-L1 assessment at baseline (e.g., due to inadequate tissue collection using fine needle aspiration), and cytological assessment of PD-L1 expression, while feasible, is not yet widely standardized in routine clinical practice (34).