The Zollinger-Ellison syndrome describes the association of:
- gastrin-producing tumours
- gastric hypersecretion
- severe peptic ulcer disease
Usually, the tumour is situated in the pancreas but may arise in the upper small intestine or gastric antrum. 60% of the tumours are malignant. 10% are multiple
Patients with the Zollinger-Ellison syndrome may develop diarrhoea and malabsorption due to inhibition of pancreatic lipase by the excessive gastric acid. This syndrome occurs in about 0.1% of patients with duodenal ulcer disease.
Gastrinomas may occurs as part of a multiple endocrine neoplasia syndrome and so screening for pituitary adenomas, parathyroid tumours and other pancreatic tumours may be indicated
- approximately 20–25% of gastrinoma patients have MEN-I syndrome (1)
Diagnosis and investigation of gatrinomas:
- high fasting plasma gastrin
- high gastric acid secretion
- diminished response to pentagastrin
- demonstrable pancreatic or gastrointestinal tumour - by CT or venous sampling for gastrin
- more than 90% of gastrinomas have somatostatin receptors, and somatostatin receptor scintigraphy has been reported to be a especially sensitive method to image gastrinomas
Management:
- management is directed by a specialist
- most patients are managed with proton pump inhibitors
- octreotide can also control acid hypersecretion in patients with Zollinger-Ellison syndrome - this treatment modality has a favourable outcome on the patients' prognosis and survival (1)
- total gastrectomy and parietal cell vagotomy are only seldom necessary
- surgical resection of the primary tumour(s) may improve prognosis and even result in a complete cure (1)
- note also that there is a general consensus that curative surgery should also be aimed for in metastatic disease, including metastatic disease ‘localized’ to the liver (1)
- systemic chemotherapy is indicated in patients with metastatic disease
- liver transplantation may be considered in patients with no extrahepatic metastases
Notes:
- in diagnosing gastrinoma, the measurement of basal and maximal gastric acid output is mandatory to distinguish it from secondary hypergastrinaemia
- at the time of diagnosis of a gastrinoma, 60–80% have metastasized to regional lymph nodes or to the liver.
Reference:
- de Herder WW and Lamberts SWJ. Best Practice & Research Clinical Endocrinology & Metabolism 2004; Volume 18(4): 477-495.