The high expression of PD-L1 (and to a lesser extent, PD-L2) on tumor cells is correlated with poor prognosis and poor survival in various cancer types, including renal cell carcinoma, pancreatic carcinoma, hepatocellular carcinoma, ovarian carcinoma, and non-small-cell lung cancer (NSCLC) [6–10]. The gene discussed is PDCD1LG2; the disease is non-small cell lung carcinoma.