Immuno-checkpoint inhibitors in metastatic esophago-gastric cancer

Esophageal and gastric cancer show an incidence of 3–4 and 5–6 cases/100,000 people respectively in western countries (1), being the eighth and fifth most common neoplasia worldwide and among the sixth most common cause of cancer related deaths. It is also 3 to 4 times more frequent in men than in women. The most common site of esophageal cancer is the lower third of the organ, involving the esophago-gastric junction (EGJ) with increasing incidence over the last four decades (2); instead the incidence of non-cardia gastric cancers has declined and this trend is likely related to improvements in diet and control of chronic H. pylori infection and concurring increased risk factors such as gastroesophageal reflux disease and obesity. Adenocarcinomas are the most common histological subtype of EGJ cancers (90%) (3).