Recently, a phase III trial was conducted to evaluate the efficacy of addition of pembrolizumab, an immune checkpoint inhibitor, to pemetrexed/platinum-based drugs in patients with PS 0-1 stage IV NSCLC without epidermal growth factor receptor (EGFR) mutation or anaplastic lymphoma kinase (ALK) translocation (KEYNOTE-189) [22]. This evidence concerns the gene ALK and non-small cell lung carcinoma.