Hypervascular pancreatic mass with multiple peptic ulcers and thickened folds
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Best imaging tool
Helical CT or MR for pancreas and possible metastasis
Endoscopic ultrasonography for additional primary sites; guides biopsy
TOP DIFFERENTIAL DIAGNOSES
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Helicobacter pylori gastritis
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Gastric metastases and lymphoma
PATHOLOGY
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20-60% of cases are associated with multiple endocrine neoplasia type 1 (MEN1)
CLINICAL ISSUES
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Most common signs/symptoms
Pain, increased acidity, severe reflux, diarrhea, upper gastrointestinal tract ulcers
Gastrinomas are often multiple (60%), malignant (60%), and metastatic (30-50%)
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Hypergastrinemia is hallmark of Zollinger-Ellison syndrome (ZES)
Serum gastrin level of > 1,000 pg/mL is virtually diagnostic of ZES
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Prognosis
Good with surgical resection of primary gastrinoma
Poor if gastrinoma, liver metastases, or ulcers recur after surgery
TERMINOLOGY
Abbreviations
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Zollinger-Ellison syndrome (ZES)
Definitions
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Severe peptic ulcer disease associated with marked ↑ in gastric acid due to gastrin-producing endocrine tumor (gastrinoma) of pancreas
IMAGING
General Features
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Best diagnostic clue
Hypervascular pancreatic mass with multiple peptic ulcers and thickened folds
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Location
Gastrinoma: Pancreas (75%), duodenum (15%), and liver and ovaries (10%)
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Common site: Gastrinoma triangle
Superiorly: Cystic and common bile ducts
Inferiorly: 2nd and 3rd parts of duodenum
Medially: Junction of pancreatic neck and body
Ulcers: Stomach and duodenal bulb (75%), postbulbar and jejunum (25%)
Radiographic Findings
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Barium studies: Gastric, duodenal, and proximal jejunum
Large volume of fluid dilutes barium and compromises mucosal coating
Markedly thickened gastric folds
Peptic ulcers: Round or ovoid barium collections surrounded by thin or thick radiolucent rim (edematous mucosa) and radiating folds
CT Findings
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Gastrinomas
Small or large, heterogeneous density lesion, ± cystic and necrotic areas, ± calcification
Liver metastases are common
Hypervascular (primary and secondary) lesions ± local or vascular invasion on arterial and portal venous phase
Inflammatory changes in stomach, duodenum, and proximal small bowel
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Thickened gastric, duodenal, and jejunal folds
Signs of ulcer penetration
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Wall thickening, luminal narrowing of stomach and duodenum
Signs of ulcer perforation
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Free air in abdomen (from a duodenal or antral ulcer) or lesser sac (from a gastric ulcer)
MR Findings
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T1WI
Hypointense pancreatic nodule on fat-saturated sequence
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T2WI
Hyperintense on spin-echo sequence
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Both primary and metastatic tumors
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T1WI C+
Hyperintense, hypervascular on fat-saturated delayed spin-echo sequence
Ultrasonographic Findings
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Endoscopic ultrasonography (EUS)
Detects small gastrinomas better than CT or MR
Usually homogeneously hypoechoic mass
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Intraoperative ultrasonography
Detects very small tumors (75-100% sensitivity)