Pancreatic Rest (Ectopic Pancreas)

A. Definition

• Ectopic pancreas refers to pancreatic tissue located outside the normal pancreas.
• It is a congenital anomaly due to misplacement during embryogenesis.
• Histologically, it may contain acini, ducts, and occasionally islets, though exocrine elements predominate.

B. Common Locations

• Found in 0.5–13% of autopsy studies; often an incidental finding.
• Most common sites:
  • Stomach (especially prepyloric antrum) — up to 75–90% of cases.
  • Duodenum
  • Meckel diverticulum
  • Less commonly: jejunum, ileum, colon, esophagus, biliary tree, mesentery, spleen, liver, lung.

C. Clinical Presentation

• Often asymptomatic.
• When symptomatic, may present with:
  • Epigastric or abdominal pain
  • Dyspepsia
  • Gastrointestinal bleeding
  • Pyloric obstruction
  • Rarely: nausea, vomiting, jaundice, or pancreatitis

D. Complications (Rare)

• Ulceration
• Stenosis
• Intussusception
• Obstruction
• Rarely, malignant transformation or pancreatic neoplasms within ectopic tissue

E. Diagnosis

• Often discovered incidentally during imaging or endoscopy.
• Diagnostic tools:
  • Upper GI x-ray or endoscopy: smooth, submucosal nodule, often centrally umbilicated and prepyloric.
  • CT or MRI: may help differentiate from other submucosal lesions.
  • Histologic confirmation via biopsy or resection is definitive.

F. Treatment

• Asymptomatic cases: typically require no intervention.
• Symptomatic or complicated cases:
  • Endoscopic resection (e.g., snare polypectomy or band ligation) if confined to mucosa/submucosa.
  • Surgical resection if deeper layers (e.g., muscularis propria) are involved or malignancy is suspected.