PDCD1 and kidney cancer: In tumors such as kidney cancer, PD-L1 expression on the tumor cells has been correlated with tumor aggressiveness and shorter patient survival, but this did not translate into longer survival in “high” PD-L1-expressing kidney tumors when treatment with PD-1 blockade (nivolumab) was compared to everolimus in patients who had previously been treated with a VEGF tyrosine kinase inhibitor [4, 32].