MEN1 and gastric neuroendocrine tumor G1: A total of 62% had gastric ECL hyperplasia which was mild in most patients, 12% had small gastric carcinoid tumors [313], with increases in serum gastrin to only 206 pg/mL These percentages are significantly less frequent than reported in the NIH prospective study of MEN1/ZES patients [344] and less than reported in a number of older studies [258,347,359].