Mehta R, et al. – In this evidence-based review, researchers assessed the place of pembrolizumab among therapies employed in clinical practice to treat patients with gastric and gastroesophageal junction (GEJ) cancer. Pembrolizumab is the first immunotherapy to be approved by US Food and Drug Administration for programmed death ligand 1 (PD-L1) expressing gastric and GEJ cancers after they have progressed on ≥ 2 prior lines of treatment. While PD-L1 positivity does not define a tumor’s responsiveness to pembrolizumab, PD-L1-positive tumors were found to have better overall response rates. In addition to good tolerability, pembrolizumab demonstrated a favorable adverse events profile. However, the exact setting for pembrolizumab use has yet to be determined. When used as second-line treatment for advanced, metastatic gastric and GEJ cancers, pembrolizumab failed to improve overall survival.