In the KEYNOTE-189 trial, pembrolizumab's addition to standard chemotherapy comprising pemetrexed and a platinum-based drug resulted in significantly longer overall survival and progression-free survival than those associated with chemotherapy alone among patients with previously untreated metastatic nonsquamous NSCLC without epidermal growth factor receptor (EGFR) or anaplastic lymphoma kinase (ALK) mutations (ClinicalTrials.gov number, NCT02578680) [5]. Here, EGFR is linked to non-small cell lung carcinoma.