CD274 and urothelial carcinoma: Firstly, the PD-1/PD-L1 expression, e.g., Eckstein et al. reviewed and summarized the problems of that issue, so many aspects of PD-L1 immunohistochemistry in advanced urothelial carcinoma remain unclear and unfinished and should be refined, such as more specific data on tumor heterogeneity, cutoff values and tumor cell immunohistochemistry are needed to guide the pathologist to optimal scoring and so the clinicians for optimal treatment.