PD-L1 scoring
tumor
CPS, TUMOR
PD-L1 (VENTANA SP263 assay) IHC assessment was prospectively performed on a baseline tumor lesion on the VENTANA Benchmark at the Institut Jules Bordet (central laboratory). PD-L1 positivity threshold was set at ≥1% stained tumor and/or immune cells of any intensity relative to the tissue area (tumor and stroma). For exploratory biomarker analyses, baseline PD-L1 was retrospectively reviewed by a well-trained pathologist who was blinded for treatment group and clinical outcome. The PD-L1 staining was identified on immune versus tumor cells, and a combined positive score (CPS) defined as the number of positive tumor cells, lymphocytes, and macrophages divided by the total number of viable tumor cells multiplied by 100 was calculated