This study was performed to estimate the human radiation dosimetry for [(68)Ga]Ga-HBED-CC (PSMA-11) ((68)Ga PSMA-11).
Under an RDRC-approved research protocol, we evaluated the biodistribution and pharmacokinetics of (68)Ga PSMA-11 with serial PET imaging following intravenous administration to nine prostate cancer patients in whom clinical [(11)C]acetate PET/CT exams had been independently performed under Expanded Access IND 118,204. List-mode imaging was performed over the initial 0-10min post-injection with the pelvis in the field-of-view. Whole-body images were acquired, pelvis-to-head, at 15, 60, and 90-min post-injection. Additional images of the pelvis were acquired at 40-min and 115-min, and voided urine collected from each subject at 48-min and 120-min post-injection. Radiation dosimetry estimates were calculated from these data using the OLINDA software package.
Renal uptake was high and relatively invariant, ranging from 11% to 14% of the injected dose between 15 and 90-min post-injection. Radioactivity collected in the voided urine accounted for 14% of the injected dose over a period of 120-min. Lymph nodes and skeletal metastases suspicious for prostate cancer recurrence were detected in a greater number of patients using (68)Ga PSMA-11 than using (11)C-acetate.
Kidneys are the critical organ following (68)Ga PSMA-11 administration, receiving an estimated dose of 0.413mGy/MBq.
This study confirms that the kidneys will be the critical organ following intravenous administration of (68)Ga PSMA-11, and provided data consistent with the expectation that (68)Ga PSMA-11 will be superior to [(11)C]acetate for defining sites of recurrence in prostate cancer patients presenting with biochemical relapse.
Nuclear medicine and biology. 2016 Nov 04 [Epub ahead of print]
Mark A Green, Jacob A Eitel, James W Fletcher, Carla J Mathias, Mark A Tann, Thomas Gardner, Michael O Koch, Wendy Territo, Heather Polson, Gary D Hutchins
Department of Radiology and Imaging Sciences, Indiana University School of Medicine, Indianapolis, IN 46202, USA., Department of Radiology and Imaging Sciences, Indiana University School of Medicine, Indianapolis, IN 46202, USA. Electronic address: ., Department of Urology, Indiana University School of Medicine, Indianapolis, IN 46202, USA.