Based on these results, pembrolizumab, in 2017, was granted accelerated Food and Drug Administration (FDA)-approval as a third-line therapy for patients with locally advanced or metastatic G/GEJ adenocarcinoma whose tumors express a CPS of ≥1 using the PD-L1 immunohistochemistry (IHC) 22C3 pharmDx assay [2,18]. The gene discussed is CD274; the disease is gastroesophageal junction adenocarcinoma.