ALK and non-small cell lung carcinoma: Based on the results of the Keynote-189 study (23), the addition of pembrolizumab to standard chemotherapy with pemetrexed and platinum significantly prolonged progression-free survival (PFS) and overall survival (OS) in previously untreated patients with advanced non-squamous NSCLC without EGFR or ALK mutations, regardless of PD-L1 expression levels.