Endocrine Abstracts

JOINT3712

Background: The terms gastrinoma and Zollinger-Ellison syndrome (ZES) have been frequently used as synonymous. However, gastrinomas are neuroendocrine tumors that secrete gastrin, whereas ZES refers to the clinical manifestations produced by hypergastrinemia.

Material and methods: We aimed to analyze the characteristics of patients diagnosed with gastrinomas. Between 2018 and 2024, 6 patients were diagnosed with gastrinomas in our center. They were evaluated based on clinically significant symptoms, serum gastrin level, neuroendocrine markers and with the aid of imaging such as abdominal CT or MRI, EUS, Tektrotyd scintigraphy and had genetic counseling and were tested for inherited genetic syndromes. Surgery was performed according to the localization of the tumors.

Results: Six patients with a gastrinoma diagnosis were included, four out of which had ZES. The patients had a mean age of 59 years, 50% were women, with an average BMI of 30.51 kg/m². At diagnosis, the median level of gastrin was 292 pg/ml and all of the patients had abdominal pain, 66.67% weight loss, 50% diarrhea and one had upper gastrointestinal bleed. Most common sites of lesion were gastric and duodenal (33% each) followed by pancreatic site and one patient had no evidence of primary tumor. Five patients underwent surgical treatment with histological confirmation and had controlled neuroendocrine markers and gastrin levels after surgical treatment, while the sixth had an unknown primary lesion. Two patients (33%) have metastasis: mesenteric and pancreatic and no patient has an inherited genetic syndrome. All patients were controlled with long-acting somatostatin analogues and proton pump inhibitors.

Conclusions: Gastrinoma diagnosis is quite challenging as its symptoms can frequently be nonspecific. Two thirds of the patients evaluated in our center with a diagnosis of gastrinoma had ZES. Weight loss and other gastrointestinal manifestations were almost as frequent and a third had metastasis.