Immunotherapy in gastric adenocarcinoma - a rapidly evolving treatment landscape.

Gastric cancer (GC) ranks as the fifth most common cancer diagnosed worldwide. Despite advances in treatment, the prognosis for patients remains poor. Immune checkpoint inhibitors have been increasingly utilised across all settings in the treatment of GC and gastroesophageal junction (GEJ) adenocarcinomas; from perioperative treatment of resectable early-stage G/GEJ cancers to combination with chemotherapy and targeted agents in metastatic disease. This review aims to summarise the molecular subtypes of GC, outline the key evidence for the use of immunotherapy in early and advanced stage settings and discuss biomarkers and novel immunotherapeutics for GC.