Lu S, et al. - Researchers assessed studies evaluating programmed cell death ligand 1 (PD-L1) immunohistochemistry (IHC), tumor mutational burden (TMB), gene expression profiling (GEP), and multiplex immunohistochemistry/immunofluorescence (mIHC/IF) with respect to their diagnostic accuracy in predicting response to anti– programmed cell death 1 (PD-1)/PD-L1 therapy in this systematic review and meta-analysis. For every assay modality, they assessed summary receiver operating characteristic curves; their related area under the curve (AUC); pooled sensitivity, specificity, positive and negative predictive values, and positive and negative likelihood ratios. As far as prediction of response to anti–PD-1/PD-L1 therapy was concerned, comparable AUCs were shown by TMB, PD-L1 IHC, and GEP in this meta-analysis. Compared with PD-L1 IHC, TMB, or GEP alone, improved performance was observed in relation to mIHC/IF and multimodality biomarker strategies.