<prompt> Not a feature of ZES?Diarrhea non-responsive to fastingEpigastric painLarge gastric ulcerSecretin study is the investigation of choice  <response>: Feature of ZES. Diarrhea non- responsive to fasting secretory diarrhea Epigastric pain 2nd pa of Duodenum, Multiple duodenum ulcer Not present in stomach Secretin study in the IOC - BAOMAO 0.6 