CD274 and neoplasm: PD-L1 expression was assessed during screening using the PD-L1 IHC 22C3 pharmDx kit (Agilent, Carpinteria, CA, United States of America). The measure of expression was the combined positive score (CPS), defined as the ratio of PD-l1–positive cells (tumor cells, lymphocytes, and macrophages) out of the total number of tumor cells *100. PD-L1 positivity was defined as CPS ≥1 (previously reported as and equivalent to CPS ≥1%)