title: Biodistribution of the ¹⁸F-FPPRGD₂ PET radiopharmaceutical in cancer patients: an atlas of SUV measurements.
abstract: OBJECTIVE
  The aim of this study was to investigate the biodistribution of 2-fluoropropionyl-labeled PEGylated dimeric arginine-glycine-aspartic acid (RGD) peptide (PEG3-E[c{RGDyk}]2) ((18)F-FPPRGD2) in cancer patients and to compare its uptake in malignant lesions with (18)F-FDG uptake.
  
  
  METHODS
  A total of 35 patients (11 men, 24 women, mean age 52.1 ± 10.8 years) were enrolled prospectively and had (18)F-FPPRGD2 PET/CT prior to treatment. Maximum standardized uptake values (SUVmax) and mean SUV (SUVmean) were measured in 23 normal tissues in each patient, as well as in known or suspected cancer lesions. Differences between (18)F-FPPRGD2 uptake and (18)F-FDG uptake were also evaluated in 28 of the 35 patients.
  
  
  RESULTS
  Areas of high (18)F-FPPRGD2 accumulation (SUVmax range 8.9 - 94.4, SUVmean range 7.1 - 64.4) included the bladder and kidneys. Moderate uptake (SUVmax range 2.1 - 6.3, SUVmean range 1.1 - 4.5) was found in the choroid plexus, salivary glands, thyroid, liver, spleen, pancreas, small bowel and skeleton. Compared with (18)F-FDG, (18)F-FPPRGD2 showed higher tumor-to-background ratio in brain lesions (13.4 ± 8.5 vs. 1.1 ± 0.5, P < 0.001), but no significant difference in body lesions (3.2 ± 1.9 vs. 4.4 ± 4.2, P = 0.10). There was no significant correlation between the uptake values (SUVmax and SUVmean) for (18)F FPPRGD2 and those for (18)F-FDG.
  
  
  CONCLUSIONS
  The biodistribution of (18)F-FPPRGD2 in cancer patients is similar to that of other RGD dimer peptides and it is suitable for clinical use. The lack of significant correlation between (18)F-FPPRGD2 and (18)F-FDG uptake confirms that the information provided by each PET tracer is different.
authors.affiliation: Division of Nuclear Medicine and Molecular Imaging, Department of Radiology, Stanford University, Stanford, CA 300 Pasteur Drive, C21, Stanford, CA, 94305-5281, USA. ryogom@stanford.edu.|Molecular Imaging Program at Stanford (MIPS), Department of Radiology, Stanford University, Stanford, CA, USA. ryogom@stanford.edu.
authors.forename: Ryogo
authors.initials: R
authors.lastname: Minamimoto
authors.affiliation: Division of Nuclear Medicine and Molecular Imaging, Department of Radiology, Stanford University, Stanford, CA 300 Pasteur Drive, C21, Stanford, CA, 94305-5281, USA.|Molecular Imaging Program at Stanford (MIPS), Department of Radiology, Stanford University, Stanford, CA, USA.
authors.forename: Mehran
authors.initials: M
authors.lastname: Jamali
authors.affiliation: Division of Nuclear Medicine and Molecular Imaging, Department of Radiology, Stanford University, Stanford, CA 300 Pasteur Drive, C21, Stanford, CA, 94305-5281, USA.
authors.forename: Amir
authors.initials: A
authors.lastname: Barkhodari
authors.affiliation: Division of Nuclear Medicine and Molecular Imaging, Department of Radiology, Stanford University, Stanford, CA 300 Pasteur Drive, C21, Stanford, CA, 94305-5281, USA.
authors.forename: Camila
authors.initials: C
authors.lastname: Mosci
authors.affiliation: Division of Nuclear Medicine and Molecular Imaging, Department of Radiology, Stanford University, Stanford, CA 300 Pasteur Drive, C21, Stanford, CA, 94305-5281, USA.
authors.forename: Erik
authors.initials: E
authors.lastname: Mittra
authors.affiliation: Molecular Imaging Program at Stanford (MIPS), Department of Radiology, Stanford University, Stanford, CA, USA.
authors.forename: Bin
authors.initials: B
authors.lastname: Shen
authors.affiliation: Molecular Imaging Program at Stanford (MIPS), Department of Radiology, Stanford University, Stanford, CA, USA.
authors.forename: Frederick
authors.initials: F
authors.lastname: Chin
authors.affiliation: Division of Nuclear Medicine and Molecular Imaging, Department of Radiology, Stanford University, Stanford, CA 300 Pasteur Drive, C21, Stanford, CA, 94305-5281, USA.|Molecular Imaging Program at Stanford (MIPS), Department of Radiology, Stanford University, Stanford, CA, USA.
authors.forename: Sanjiv Sam
authors.initials: SS
authors.lastname: Gambhir
authors.affiliation: Division of Nuclear Medicine and Molecular Imaging, Department of Radiology, Stanford University, Stanford, CA 300 Pasteur Drive, C21, Stanford, CA, 94305-5281, USA. aiagaru@stanford.edu.
authors.forename: Andrei
authors.initials: A
authors.lastname: Iagaru
mesh_terms: D001692:Biological Transport; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000000981:diagnostic imaging* / Q000378:metabolism*; D009842:Oligopeptides / Q000493:pharmacokinetics*; D010456:Peptides, Cyclic / Q000493:pharmacokinetics*; D049268:Positron-Emission Tomography; D019275:Radiopharmaceuticals / Q000493:pharmacokinetics*; D014018:Tissue Distribution
chemical_list: C574086:FPP(RGD)2; D009842:Oligopeptides; D010456:Peptides, Cyclic; D019275:Radiopharmaceuticals; C047981:arginyl-glycyl-aspartic acid
keywords: 18F-FPPRGD2 PET/CT; Angiogenesis; Atlas; PET/CT; αvβ3 integrin expression