A condition in which tumours are formed in the islet cells of the pancreas together with peptic ulcers [Described 1955. After Robert Milton Zollinger (b. 1903), Professor of Surgery at Ohio State University, USA; Edwin H. Ellison (1918-70), Associate Professor of Surgery at Ohio State University, USA.]
Zollinger-Ellison syndrome (ZES) is a rare digestive disorder that can cause tumors in the duodenum (top of small intestine) and pancreas and can cause stomach-duodenal ulcers. Cancerous tumors secrete serum gastrin, causing the stomach to produce excessive acid, which is responsible for peptic ulcers. The actual cause of ZES is unknown, but it may be associated with an abnormal tumor-suppressing gene.