Summary

• Gastrin-producing neuroendocrine tumour that causes gastric acid hypersecretion and peptic ulcer disease.
• Can be sporadic or associated with multiple endocrine neoplasia syndrome type 1.
• Common presentation includes refractory peptic ulcer disease, abdominal pain, diarrhoea, and gastro-oesophageal disease.
• The main goal of treatment is control of gastric hypersecretion with proton-pump inhibitors.
• The most common cause of morbidity and mortality is metastatic gastrinoma.