Imaging tests, such as computed tomography (CT) scan or ultrasound, can also be used to find and diagnose an insulinoma. Zollinger-Ellison syndrome (ZES) is a rare digestive disease caused by a tumor ...

Since such gastrin measurements are strong indicators of a gastrin producing tumor, for example, a gastrinoma, some patients without a history of ulcers or signs of a multiple endocrine dysplasia ...