The results are generally similar to those in other large series of patients with ZES [20,29,86,125,126,179,180,181,182,183,184,185,186] in regard to age at either onset or diagnosis of ZES, gender, percentage with MEN1, presentation of symptoms, disease duration, frequency of prior gastric acid reduction surgery, fasting gastrin levels, basal and maximal acid secretory rates, as well as tumor location and extent. This evidence concerns the gene GAST and Zollinger-Ellison syndrome.