MEN1 and Zollinger-Ellison syndrome: The universal frequency of the gastric ECL proliferative changes found in this large perspective study of MEN1/ZES patients [61] is similar to results with other smaller studies (usually < 20 MEN1/ZES patients), which also reported 92–100% of MEN1/ZES patients had such changes [62,163,164,165], but differ from other small studies, which reported these changes in an only 14–65% of MEN1/ZES patients [166,200].