In this retrospective study, we identified 283 patients with metastatic nonsquamous NSCLC without EGFR or ALK genomic aberrations, and with good performance status (ECOG PS of 0 or 1), who received first-line pembrolizumab plus pemetrexed-carboplatin at US oncology practices following regulatory approval in May 2017. This evidence concerns the gene ALK and non-small cell lung carcinoma.