Comparison of 68Ga-DOTATOC PET and 111In-DTPAOC (Octreoscan) SPECT in patients with neuroendocrine tumours

Eur J Nucl Med Mol Imaging. 2007 Oct;34(10):1617-26. doi: 10.1007/s00259-007-0450-1. Epub 2007 May 23.


Purpose: Neuroendocrine tumours (NETs) can be imaged with scintigraphy using radiolabelled somatostatin analogues. The aim of our study was to compare the value of (68)Ga-DOTATOC PET and (111)In-DTPAOC SPECT (Octreoscan) in the detection of NET manifestations.

Methods: Twenty-seven NET patients were prospectively examined. (68)Ga-DOTATOC PET and (111)In-DTPAOC SPECT were performed using standard techniques. Treatment was not applied in between. Mean and maximum standardised uptake values (SUVs) were calculated for PET findings. Tumour/non-tumour ratios were calculated for SPECT findings. Findings were compared by a region-by-region analysis and verified with histopathology, CT and MRI within 21 days.

Results: SUVs of positive lesions on (68)Ga-DOTATOC PET ranged from 0.7 to 29.3 (mean SUV) and from 0.9 to 34.4 (maximum SUV). Tumour/non-tumour ratios on (111)In-DTPAOC SPECT ranged from 1.8 to 7.3. In imaging lung and skeletal manifestations, (68)Ga-DOTATOC PET was more efficient than (111)In-DTPAOC SPECT. All discrepant lung findings and 77.8% of discrepant osseous findings were verified as true positive PET interpretations. In regional comparison of liver and brain, (68)Ga-DOTATOC PET and (111)In-DTPAOC SPECT were identical. In lymph nodes, the pancreas and the gastro-intestinal system, different values of the two techniques were not indicated in regional analyses. In a single patient, surgical interventions were changed on the basis of (68)Ga-DOTATOC PET findings.

Conclusion: (68)Ga-DOTATOC PET is superior to (111)In-DTPAOC SPECT in the detection of NET manifestations in the lung and skeleton and similar for the detection of NET manifestations in the liver and brain. (68)Ga-DOTATOC PET is advantageous in guiding the clinical management.

Publication types

  • Comparative Study
  • Evaluation Study

MeSH terms

  • Adult
  • Aged
  • Female
  • Humans
  • Male
  • Middle Aged
  • Neuroendocrine Tumors / diagnostic imaging*
  • Octreotide / analogs & derivatives*
  • Organometallic Compounds*
  • Positron-Emission Tomography / methods*
  • Radiopharmaceuticals
  • Reproducibility of Results
  • Sensitivity and Specificity
  • Somatostatin / analogs & derivatives*
  • Tomography, Emission-Computed, Single-Photon / methods*


  • Organometallic Compounds
  • Radiopharmaceuticals
  • Somatostatin
  • pentetreotide
  • Octreotide