Data from clinical trials of ICI monotherapy showed inconsistent results in terms of associations between response and PD-L1 expression in urothelial carcinoma,11–14 which may be caused by differences in procedure of tissue collection and fixation, antibody and assay used for PD-L1 test, definition of PD-L1 expression, and cut-off for PD-L1 positivity. Here, CD274 is linked to urothelial carcinoma.