PD-1/PD-L1 inhibitors such as nivolumab, pembrolizumab and atezolizumab are now approved for the first and second line treatment of metastatic NSCLC (without actionable driver mutations) and SCLC, and as a maintenance treatment after chemoradiotherapy in inoperable stage III NSCLC (durvalumab). The gene discussed is PDCD1; the disease is non-small cell lung carcinoma.