Management of Gastrinoma

Abstract

Gastrinoma is a functioning neuroendocrine tumor resulting in the oversecretion of gastrin. Patients often present with abdominal pain, diarrhea, and reflux. They are most often sporadic but may be associated with multiple endocrine neoplasia type 1 (MEN1) in a minority of cases. Biochemical testing for hypergastrinemia includes a fasting serum gastrin level. If the results are equivocal, a secretin stimulation test can be performed. After the diagnosis is confirmed, cross-sectional imaging should be performed which will most often localize the tumor to the gastrinoma triangle. Further localization may include somatostatin receptor scintigraphy and endoscopic ultrasound. Medical treatment should be guided toward decreasing the burden of hypersecretion with either proton pump inhibitors or histamine-2 receptor blockers. For isolated, sporadic gastrinomas, treatment includes surgical resection. However, roughly 50% of patients with have metastatic disease at the time of diagnosis. The approach for patients with MEN1 is less clear.