Imaging of neuroendocrine gastro-entero-pancreatic tumours using radiolabelled somatostatin analogues

Ital J Gastroenterol Hepatol. 1999 Oct;31 Suppl 2:S190-4.

Abstract

Neuroendocrine tumours of the gastro-entero-pancreatic tract are an uncommon clinical entity and are believed to arise from the endocrine cells of the gastrointestinal tract. Somatostatin receptor imaging is a diagnostic tool which allows visualization of somatostatin receptor bearing tumours. This scintigraphic procedure is performed with indium-111 labelled octreotide, a somatostatin analogue, chelated with diethylene triamine penta-acetic acid. Radionuclide imaging consists in detecting the biodistribution of somatostatin receptors, normally expressed on the cell surface of neuroendocrine gastro-entero-pancreatic tumours. To date, five types of this receptor have been cloned: indium-111-labelled-pentetreotide can visualize tumours expressing type 2 and 5 receptors. The results of our study, which involved 81 neuroendocrine gastro-entero-pancreatic tumour patients, confirm the superior sensitivity of somatostatin receptor imaging (61%) for primary tumour evaluation with respect to conventional imaging modalities such as computed tomography (40%) or ultrasound (28%). Scintigraphic findings in metastatic liver disease proved to have a sensitivity of 89% for somatostatin receptor imaging, versus 81% and 88% for computed tomography and ultrasound, respectively. In 23% of patients, lesions were found with somatostatin receptor imaging which had been missed using the other diagnostic modalities; in 26% of the patients the therapeutic approach was modified after somatostatin receptor imaging.

Publication types

  • Clinical Trial
  • Comparative Study

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Aged, 80 and over
  • Female
  • Gastrointestinal Neoplasms / diagnosis
  • Gastrointestinal Neoplasms / diagnostic imaging*
  • Humans
  • Magnetic Resonance Imaging
  • Male
  • Middle Aged
  • Neuroendocrine Tumors / diagnosis
  • Neuroendocrine Tumors / diagnostic imaging*
  • Octreotide
  • Pancreatic Neoplasms / diagnosis
  • Pancreatic Neoplasms / diagnostic imaging*
  • Receptors, Somatostatin / analysis*
  • Sensitivity and Specificity
  • Tomography, Emission-Computed, Single-Photon / methods*
  • Tomography, X-Ray Computed

Substances

  • Receptors, Somatostatin
  • Octreotide