PDCD1 and non-small cell lung carcinoma: In this context, it has recently been shown that patients with metastatic NSCLC with expression of PD-L1 on at least 50% of tumor cells, treatment with pembrolizumab (an anti-PD-1 antibody) is associated with considerably longer progression-free and overall survival, as well as with fewer adverse events compared with platinum-based chemotherapy (11).