GAST and Zollinger-Ellison syndrome: These results show that, despite prolonged chronic hypergastrinemia averaging 14 years in the large NIH study reviewed above [25] and the fact that the ZES patients in more than half of the cases had high fasting serum gastrin (FSG) levels at least double that seen typically in patients being treated with PPIs, with many ZES patients with FSG > 5–10 levels (Figure 1), the occurrence of gastric carcinoids in the sporadic ZES patients was very uncommon.