European Journal of Nuclear Medicine

, Volume 28, Issue 12, pp 1751–1757

Biokinetics and imaging with the somatostatin receptor PET radioligand 68Ga-DOTATOC: preliminary data

Authors

  • M. Hofmann
    • Department of Nuclear Medicine, Hannover University Medical School, Carl-Neuberg-Strasse 1, 30625 Hannover
  • H. Maecke
    • Radiochemistry, Department of Radiology, Kantonspittal, Basel
  • A. Börner
    • Department of Nuclear Medicine, Hannover University Medical School, Carl-Neuberg-Strasse 1, 30625 Hannover
  • E. Weckesser
    • Department of Nuclear Medicine, Hannover University Medical School, Carl-Neuberg-Strasse 1, 30625 Hannover
  • P. Schöffski
    • Department of Haematology and Oncology, Hannover University Medical School, Hannover
  • M. Oei
    • Department of Nuclear Medicine, Hannover University Medical School, Carl-Neuberg-Strasse 1, 30625 Hannover
  • J. Schumacher
    • German Cancer Research Centre, Heidelberg
  • M. Henze
    • German Cancer Research Centre, Heidelberg
  • A. Heppeler
    • Radiochemistry, Department of Radiology, Kantonspittal, Basel
  • G. Meyer
    • Department of Nuclear Medicine, Hannover University Medical School, Carl-Neuberg-Strasse 1, 30625 Hannover
  • W. Knapp
    • Department of Nuclear Medicine, Hannover University Medical School, Carl-Neuberg-Strasse 1, 30625 Hannover
Original Article

DOI: 10.1007/s002590100639

Cite this article as:
Hofmann, M., Maecke, H., Börner, A. et al. Eur J Nucl Med (2001) 28: 1751. doi:10.1007/s002590100639

Abstract

Somatostatin (SMS) scintigraphy is widely used for the detection and staging of neuroendocrine tumours. Because of its superior imaging properties, there is growing interest in the use of positron emission tomography (PET) technology for SMS scintigraphy. This study addressed the production of gallium-68 DOTATOC, its biokinetics and its clinical performance in detecting SMS-positive tumours and metastases. A preparation protocol was developed, yielding 40% overall incorporation of 68Ga into the peptide (DOTATOC). After column filtration, the radiochemical purity exceeded 98%. Eight patients with histologically verified carcinoid tumours were injected with 80–250 MBq of this tracer. PET acquisition was initiated immediately after administration and carried out until 3 h post injection. Images were quantitated using standardised uptake values and target to non-target ratios. Prior to 68Ga-DOTATOC PET, all patients underwent indium-111 octreotide planar and single-photon emission tomographic (SPET) imaging. Arterial activity elimination was bi-exponential, with half-lives of 2.0 (±0.3) min and 48 (±7) min. No radioactive metabolites were detected within 4 h in serum. Maximal tumour activity accumulation was reached 70±20 min post injection. Kidney uptake averaged <50% compared with spleen uptake. Of 40 lesions predefined by computed tomography and/or magnetic resonance imaging, 68Ga-DOTATOC PET identified 100%, whereas 111In-octreotide planar and SPET imaging identified only 85%. Tumour to non-tumour ratios ranged from >3:1 for liver (111In-octreotide: 1.5:1) to 100:1 for CNS (111In-octreotide: 10:1). With 68Ga-DOTATOC >30% additional lesions were detected. It is concluded that PET using 68Ga-DOTATOC results in high tumour to non-tumour contrast and low kidney accumulation and yields higher detection rates as compared with 111In-octreotide scintigraphy.

Carcinoid tumours Gallium-68 DOTATOC Somatostatin receptor PET Radiopeptides Indium-111 octreotide

Copyright information

© Springer-Verlag 2001