RT Journal Article
SR Electronic
T1 Biodistribution and Radiation Dosimetry for the Chemokine Receptor CXCR4-Targeting Probe <sup>68</sup>Ga-Pentixafor
JF Journal of Nuclear Medicine
JO J Nucl Med
FD Society of Nuclear Medicine
SP 410
OP 416
DO 10.2967/jnumed.114.151647
VO 56
IS 3
A1 Ken Herrmann
A1 Constantin Lapa
A1 Hans-Juergen Wester
A1 Margret Schottelius
A1 Christiaan Schiepers
A1 Uta Eberlein
A1 Christina Bluemel
A1 Ulrich Keller
A1 Stefan Knop
A1 Saskia Kropf
A1 Andreas Schirbel
A1 Andreas K. Buck
A1 Michael Lassmann
YR 2015
UL http://jnm.snmjournals.org/content/56/3/410.abstract
AB 68Ga-pentixafor is a promising PET tracer for imaging the expression of the human chemokine receptor 4 (CXCR4) in vivo. The whole-body distribution and radiation dosimetry of 68Ga-pentixafor were evaluated. Methods: Five multiple-myeloma patients were injected intravenously with 90–158 MBq of 68Ga-pentixafor (mean ± SD, 134 ± 25 MBq), and a series of 3 rapid multiple-bed-position whole-body scans were acquired immediately afterward. Subsequently, 4 static whole-body scans followed at 30 min, 1 h, 2 h, and 4 h after administration of the radiopharmaceutical. Venous blood samples were obtained. Time-integrated activity coefficients were determined from multiexponential regression of organ region-of-interest data normalized to the administered activity, for example, the time-dependent percentages of the injected activity per organ. Mean organ-absorbed doses and effective doses were calculated using OLINDA/EXM. Results: The effective dose based on 150 MBq of 68Ga-pentixafor was 2.3 mSv. The highest organ-absorbed doses (for 150 MBq injected) were found in the urinary bladder wall (12.2 mGy), spleen (8.1 mGy), kidneys (5.3 mGy), and heart wall (4.0 mGy). Other organ mean absorbed doses were as follows: 2.7 mGy, liver; 2.1 mGy, red marrow; 1.7 mGy, testes; and 1.9 mGy, ovaries. Conclusion: 68Ga-pentixafor exhibits a favorable dosimetry, delivering absorbed doses to organs that are lower than those delivered by 18F-FDG– or 68Ga-labeled somatostatin receptor ligands.