What is Zollinger-Ellison syndrome and how to diagnose it?

What is Zollinger-Ellison syndrome and how to diagnose it?

Publication date: 18-04-2023

Updated on: 18-04-2023

Topic: Gastroenterology

Estimated reading time: 1 min

Zollinger-Ellison syndrome is a very rare clinical condition with an incidence of 1 patient per 1 million of population. How is it recognized, how is it treated, and what are the prospects for the patient? We asked Dr. Paoletta Preatoni, head of the Clinical Gastroenterology Functional Unit of the Department of Gastroenterology and Digestive Endoscopy at Ospedale San Raffaele directed by Professor Silvio Danese.

How Zollinger-Ellison syndrome manifests itself

This is a disease in which symptoms are brought about by an overproduction of hydrochloric acid by the stomach, resulting in the onset of ulcers in the stomach, esophagus, or duodenum that lead the patient to experience epigastric pain, diarrhea, burning, difficulty swallowing food, resulting in weight loss and a general feeling of malaise.

In more serious cases, the onset of these ulcers can cause bleeding, whereby the patient may notice dark stools or vomiting with traces of blood.

Main cause of Zollinger-Ellison syndrome

The overproduction of gastric acid caused by the syndrome is related to the fact that there is overproduction of gastrin, a hormone that stimulates the stomach during the digestive phase to produce gastric juice. In this case, the trigger for this excessive production of gastrin is determined by a neuroendocrine tumor, gastrinoma.

What is a gastrinoma?

Gastrinoma is a neuroendocrine tumor that can localize in the pancreas or, more frequently, at the level of the second duodenal portion in the so-called 'gastrinoma triangle.'

In 75% of cases, this tumor is sporadic, not associated with other diseases. In the remainder, it is associated with so-called Multiple Genetic Syndromes, neuroendocrine tumors with which pituitary or parathyroid tumors may be associated.

At what age does gastrinoma arise?

The condition usually arises between the ages of 20 and 40, with no difference between males and females. Gastrinoma is hereditary only in Multiple Neuroendocrine Neoplasms, with autosomal dominant transmission.


The diagnosis is made because the patient goes to the doctor who, seeing the symptomatology compatible with that of peptic ulcer, prescribes a gastroscopy.

Unlike common ulcers, which are due to drug abuse or poor habits, in the case of Zollinger-Ellison syndrome, not a single ulcer is detected, but a multiplicity of ulcers.

Histological examination of the latter is not used to diagnose gastrinoma, which is instead detected by gastrin sampling, a painless test that usually shows very high values in patients with this syndrome. Second-level investigations such as CT and PET scans will be crucial in identifying lesions that produce this hormone.


Gastrinoma is a very rare and generally well-differentiated disease. This means that it tends to have a good prognosis, especially when associated with Multiple Genetic Syndromes.

Treatment involves the administrations of proton pump inhibitor drugs (pantoprazole and its derivatives), combined with gastroprotectants.

At the point when the gastrinoma lesion is unique and nonmetastatic, surgical removal is possible, to which radiological and chemotherapy treatment can be added if it is a metastatic lesion, depending on the degree of the pathology. 

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