A 55-year-old male with H. pylori-negative peptic ulcer disease refractory to proton pump inhibitors has a fasting serum gastrin of 1200 pg/mL (normal < 110 pg/mL). Secretin stimulation test shows a paradoxical rise in gastrin. Which classification describes the site of gastrinoma in 80% of cases?
- A Within the body and tail of the pancreas in 80% of cases
- B The gastrinoma triangle — bounded by junction of cystic duct and CBD, junction of duodenum 2nd and 3rd part, and neck/body of pancreas ✓
- C Ectopic — adrenal, ovary, or lymph nodes in 80%
- D The hepatic parenchyma as a primary hepatic gastrinoma
Explanation
The gastrinoma triangle (Passaro's triangle) is the anatomical region containing 80–90% of gastrinomas in Zollinger-Ellison syndrome. It is bounded superiorly by the junction of the cystic duct and common bile duct, inferiorly by the junction of the 2nd and 3rd parts of the duodenum, and medially by the junction of the neck and body of the pancreas. The duodenal wall is the most common single site (50–60%), followed by the pancreatic head (25–30%). A positive secretin stimulation test (paradoxical rise in gastrin > 200 pg/mL above baseline) confirms ZES. MEN1 must be excluded, especially if multiglandular or familial.
Reference: Bailey & Love's Short Practice of Surgery, 27th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.