<prompt> Answer this question truthfullyWhat are the epidemiology and demographics of Zollinger-Ellison syndrome?  <response>: <reason> The worldwide incidence of gastrinomas is about 5 to 30 cases per 100,000 individuals per year. With improved techniques for tumor detection, the annual incidence has increased. About 80 to 90 of these tumors arise in the gastrinoma triangle.Zollinger-Ellison syndrome is a disease that tends to affect the middle-aged adult population 20 - 50 years of age. Males are more commonly affected with Zollinger-Ellison syndrome than females. There is no racial predilection to Zollinger-Ellison syndrome 