Zollinger-Ellison syndrome This syndrome is mentioned here because the gastrin producing endocrine tumour is often found in the duodenal loop, although it also occurs in the pancreas, especially the head. It is a cause of persistent peptic ulceration. Before the development of potent gastric antisecretory agents, the condition was recognised by the sometimes fulminant peptic ulceration which did not respond to gastric surgery sho of total gastrectomy. It was also recognisable from gastric secretory studies in which the patient had a very high basal acid output but no marked response to pentagastrin, as the parietal cell mass was already nearly maximally stimulated by pathological levels of gastrin. The advent of proton pump inhibitors such as omeprazole has rendered this extreme endocrine condition fully controllable, but also less easily recognised. Gastrinomas may be either sporadic or associated with the autosomal dominantly inherited multiple endocrine neoplasia (MEN) type I (in which a parathyroid adenoma is almost invariable). The tumours are most commonly found in the 'gastrinoma triangle' (Passaro) defined by the junction of the cystic duct and common bile duct superiorly, the junction of the second and third pas of the duodenum inferiorly, and the junction of the neck and body of the pancreas medially (essentially the superior mesenteric aery). Many are found in the duodenal loop, presumably arising in the G cells found in Brunner's glands. It is extremely impoant that the duodenal wall is very carefully inspected endoscopically and also at operation. Very often all that can be detected is a small nodule that projects into the medial wall of the duodenum. Even malignant sporadic gastrinomas may have a very indolent course. The palliative resection of liver metastases may be beneficial and liver transplantation is practised in some centres, as for other gut endocrine tumours, with reasonable long-term results. However, the minority of tumours found to the left of the superior mesenteric aery (outside the 'triangle') seem to have a worse prognosis, more having liver metastases at presentation. In MEN type I, the tumours may be multiple and the condition is incurable. Even in this situation,as with sporadic gastrinoma, surgical treatment should be employed to remove any obvious tumours and associated lymphatic metastases, as the palliation achieved may be good. Ref: Bailey and love 27th edition Pgno : 1141