Library
Gastroenterology
·
hard
Suspected Gastrinoma (Zollinger–Ellison)
Flowchart
Play
Multiple ulcers + thick gastric folds → check gastrin off PPI.
Decision
Outcome
Decision
Endoscopy shows multiple ulcers + thick gastric folds. Next step?
✓
Stop PPI for 1 week, then check serum gastrin
✗
Check gastrin on PPI
Decision
Off-PPI gastrin?
✓
<110 pg/mL → not gastrinoma
✓
110–1000 pg/mL → secretin stimulation test
✓
>1000 pg/mL → check gastric pH off PPI
Outcome
Not gastrinoma — pursue alternative cause of refractory ulcers
Decision
Secretin stimulation test?
✓
Paradoxical gastrin rise >120 → gastrinoma
✓
Negative → not gastrinoma
Outcome
Confirmed ZES — somatostatin receptor scintigraphy or EUS to localize; surgical resection if possible
ZES is in the 'gastrinoma triangle' (junction of CBD, neck of pancreas, 2nd/3rd duodenum). Associated with MEN-1.
Decision
Gastric pH off PPI?
✓
≤4 → gastrinoma (further testing to localize)
✓
>4 → not gastrinoma
Drag to pan · scroll to navigate