CD274 and nonpapillary renal cell carcinoma: Finally, it is worth mentioning that although PD1/PD-L1 expression is the most direct factor for predicting PD1/PD-L1 inhibitor efficacy, the variability in PD-L1 expression across ccRCC indicates that assessing it as a predictive biomarker for PD1 blockade may necessitate analysis of metastatic sites.