ALK and non-small cell lung carcinoma: The phase 3 KEYNOTE-024 trial (2016) demonstrated that pembrolizumab significantly improved progression-free survival (PFS) and 6-month overall survival (OS) compared to platinum-based chemotherapy in patients with metastatic NSCLC with high PD-L1 expression (≥50%) and no EGFR/ALK alterations [27].