Biodistribution and radiation dosimetry of (68)Ga-PSMA HBED CC-a PSMA specific probe for PET imaging of prostate cancer.

Positron emission tomography (PET) agents targeting the prostate-specific membrane antigen (PSMA) are currently under broad clinical and scientific investigation. (68)Ga-PSMA HBED-CC constitutes the first (68)Ga-labelled PSMA-inhibitor and has evolved as a promising agent for imaging PSMA expression in vivo. The aim of this study was to evaluate the whole-body distribution and radiation dosimetry of this new probe.

Five patients with a history or high suspicion of prostate cancer were injected intravenously with a mean of 139.8 ± 13.7 MBq of (68)Ga-PSMA HBED-CC (range 120-158 MBq). Four static skull to mid-thigh scans using a whole-body fully integrated PET/MR-system were performed 10 min, 60 min, 130 min, and 175 min after the tracer injection. Time-dependent changes of the injected activity per organ were determined. Mean organ-absorbed doses and effective doses (ED) were calculated using OLINDA/EXM.

Injection of a standard activity of 150 MBq (68)Ga-PSMA HBED-CC resulted in a median effective dose of 2.37 mSv (Range 1.08E-02 - 2.46E-02 mSv/MBq). The urinary bladder wall (median absorbed dose 1.64E-01 mGv/MBq; range 8.76E-02 - 2.91E-01 mGv/MBq) was the critical organ, followed by the kidneys (median absorbed dose 1.21E-01 mGv/MBq; range 7.16E-02 - 1.75E-01), spleen (median absorbed dose 4.13E-02 mGv/MBq; range 1.57E-02 - 7.32E-02 mGv/MBq) and liver (median absorbed dose 2.07E-02 mGv/MBq; range 1.80E-02 - 2.57E-02 mGv/MBq). No drug-related pharmacological effects occurred.

The use of (68)Ga-PSMA HBED-CC results in a relatively low radiation exposure, delivering organ doses that are comparable to those of other (68)Ga-labelled PSMA-inhibitors used for PET-imaging. Total effective dose is lower than for other PET-agents used for prostate cancer imaging (e.g. (11)C- and (18)F-Choline).

European journal of nuclear medicine and molecular imaging. 2016 May 20 [Epub ahead of print]

Christian H Pfob, Sibylle Ziegler, Frank Philipp Graner, Markus Köhner, Sylvia Schachoff, Birgit Blechert, Hans-Jürgen Wester, Klemens Scheidhauer, Markus Schwaiger, Tobias Maurer, Matthias Eiber

Department of Nuclear Medicine, Technische Universität München, Klinikum rechts der Isar; Ismaningerstrasse 22, 81675, Munich, Germany. ., Department of Nuclear Medicine, Technische Universität München, Klinikum rechts der Isar; Ismaningerstrasse 22, 81675, Munich, Germany., Department of Nuclear Medicine, Technische Universität München, Klinikum rechts der Isar; Ismaningerstrasse 22, 81675, Munich, Germany., Department of Nuclear Medicine, Technische Universität München, Klinikum rechts der Isar; Ismaningerstrasse 22, 81675, Munich, Germany., Department of Nuclear Medicine, Technische Universität München, Klinikum rechts der Isar; Ismaningerstrasse 22, 81675, Munich, Germany., Department of Nuclear Medicine, Technische Universität München, Klinikum rechts der Isar; Ismaningerstrasse 22, 81675, Munich, Germany., Chair of Pharmaceutical Radiochemistry, Department Chemie, Technische Universität München, Walther-Meissner-Str. 3, 85748, Garching, Germany., Department of Nuclear Medicine, Technische Universität München, Klinikum rechts der Isar; Ismaningerstrasse 22, 81675, Munich, Germany., Department of Nuclear Medicine, Technische Universität München, Klinikum rechts der Isar; Ismaningerstrasse 22, 81675, Munich, Germany., Department of Urology, Technische Universität München, Klinikum rechts der Isar, Ismaninger Str. 22, 81675, Munich, Germany., Department of Nuclear Medicine, Technische Universität München, Klinikum rechts der Isar; Ismaningerstrasse 22, 81675, Munich, Germany.

E-Newsletters

Newsletter subscription

Free Daily and Weekly newsletters offered by content of interest

The fields of GU Oncology and Urology are rapidly advancing. Sign up today for articles, videos, conference highlights and abstracts from peer-review publications by disease and condition delivered to your inbox and read on the go.

Subscribe