Biomarker assessment
tumor, Tumor
TUMOR, TUMOR
Tumor samples prior to receiving any therapy were used for biomarker analysis. PD-L1 immunohistochemistry was performed on formalin-fixed paraffin-embedded tumor biopsy samples using the PD-L1 IHC 22C3 pharmDx antibody (Dako, CA). Measurement of PD-L1 expression was based on the estimated percentage of PD-L1-stained cells.