CD274 and lung cancer: The immune checkpoint inhibitor pembrolizumab demonstrated an intracranial response rate of 33% in non–small cell lung cancer (NSCLC) with PD-L1 expression above 1% (8), and a combination of the immunotherapeutic agents nivolumab and ipilimumab proven efficient in targeting melanoma brain metastases (9) has also shown promise for lung cancer brain metastases (10, 11).