Advances in immunohistochemistry staining and scoring of PD-L1 expression in tumor lesions, independent assessment of PD-L1 expression on tumor and non-tumor cells, combining PD-L1 expression scores with other parameters such as T-cell infiltration and T-cell proximity to tumor cells, tumor mutational load and signatures of IFNγ response help improve the predictive value of PD-L1 expression in tumor biopsies [176,177,178]. This evidence concerns the gene IFNG and neoplasm.