PDCD1 and renal cell carcinoma: Compared to non-specific immunotherapies for IL-2 or IL-6, immune checkpoint blockade (ICB) therapy has performed very well in the treatment of advanced RCC since it was approved as second-line therapy in 2015. A clinical trial demonstrated that the PD-L1 inhibitor avelumab and the PD-1 inhibitor pembrolizumab plus axinib with that of sunitinib had superior advantages contrasted to sunitinib in RCC (6).