Neuroendocrine tumours of the duodenum Home A-Z Health Information Health Library A-Z Neuroendocrine Tumours of The Duodenum Overview NETs can also arise in the duodenum, the first part of the small intestine. These tumours are often associated with Zollinger-Ellison syndrome (gastrin-secreting tumours), which can cause peptic ulcers, diarrhoea, and gastroesophageal reflux disease (GERD). Symptoms Abdominal pain, often related to peptic ulcers or gastritis.Diarrhoea due to gastrin secretion.Gastrointestinal bleeding, manifested as melena or hematemesis.Weight loss or nausea if the tumour is large or metastasises. Diagnosis Endoscopy: To identify the tumour and obtain a biopsy for histopathological analysis.Somatostatin receptor scintigraphy: To assess the extent of disease and metastasis.Gastrin levels: To diagnose gastrinoma in the case of excessive gastrin production. Diagnosis of NETs in the GI Tract (Oesophagus, Stomach, Duodenum): Endoscopy:The primary diagnostic tool for visualising tumours in the oesophagus, stomach, and duodenum.Biopsy is essential to confirm the diagnosis of a neuroendocrine tumour, as well as to classify it as functional or non-functional.Imaging:CT scans, MRI, and positron emission tomography (PET) scans are used for staging, detecting metastasis, and assessing the size of the tumour.Somatostatin receptor scintigraphy (SRS) or octreotide scanning may be used to detect tumours that overexpress somatostatin receptors.Laboratory tests:Plasma or urinary chromogranin A (CgA): A marker for neuroendocrine tumours, though not specific to the GI tract.Gastrin levels: In suspected gastrinoma.5-HIAA (5-hydroxyindoleacetic acid): A metabolite of serotonin, elevated in functional neuroendocrine tumours like carcinoid tumours. Treatment Surgical resection is the mainstay of treatment for localised NETs, particularly when the tumour is small and confined to the stomach, duodenum, or oesophagus.Endoscopic treatments such as endoscopic mucosal resection (EMR) may be considered for smaller, non-invasive tumours.Chemotherapy, targeted therapies, and somatostatin analogues (octreotide) are options for more advanced, metastatic, or functional NETs, particularly those associated with carcinoid syndrome or Zollinger-Ellison syndrome.