Pancreatic polypeptide-rich islets in the posterior portion of the pancreatic head--a tumor mimic in somatostatin receptor scintigraphy

Pancreas. 2014 May;43(4):648-50. doi: 10.1097/MPA.0000000000000070.

Abstract

A 74-year-old man with recurrent duodenal ulcers underwent somatostatin receptor scintigraphy (SRS) in suspicion of gastrinoma. A 2-cm area of focal uptake was visualized within the pancreatic head. Serum chromogranin A levels were elevated, but serum gastrin levels and the secretin test were normal. Computed tomography and endoscopic ultrasonography were not conclusive. After partial duodenopancreatectomy, pathological examination failed to reveal any neuroendocrine tumor. Instead, the dorsal portion of the pancreatic head was found to be densely populated by pancreatic polypeptide cell-rich islets. This area correlated with the site of tracer uptake seen on SRS. Thus, pancreatic polypeptide cell-rich islets in elderly patients should be kept in mind when interpreting SRS results to avoid unnecessary major pancreatic resections.

Publication types

  • Case Reports

MeSH terms

  • Aged
  • Biopsy
  • Diagnostic Errors*
  • Humans
  • Male
  • Multimodal Imaging / methods
  • Neuroendocrine Tumors / diagnostic imaging*
  • Neuroendocrine Tumors / metabolism
  • Neuroendocrine Tumors / surgery
  • Octreotide / analogs & derivatives*
  • Pancreatectomy
  • Pancreatic Neoplasms / diagnostic imaging*
  • Pancreatic Neoplasms / metabolism
  • Pancreatic Neoplasms / surgery
  • Pancreatic Polypeptide-Secreting Cells / diagnostic imaging*
  • Pancreatic Polypeptide-Secreting Cells / metabolism
  • Predictive Value of Tests
  • Radiopharmaceuticals*
  • Receptors, Somatostatin / metabolism*
  • Tomography, Emission-Computed, Single-Photon*
  • Tomography, X-Ray Computed
  • Unnecessary Procedures

Substances

  • Radiopharmaceuticals
  • Receptors, Somatostatin
  • indium-111-octreotide
  • Octreotide