title: ¹⁸F-FPRGD₂ PET/CT imaging of musculoskeletal disorders.
abstract: OBJECTIVE
  This work reports on musculoskeletal uptake of ¹⁸F-FPRGD₂, targeting the integrin αvβ3, in patients who had undergone ¹⁸F-FPRGD₂ positron emission tomography combined with computed tomography (PET/CT) for oncologic purposes.
  
  
  METHODS
  Whole-body ¹⁸F-FPRGD₂ PET/CT images of 62 cancer patients were retrospectively reviewed to detect foci of musculoskeletal ¹⁸F-FPRGD₂ uptake. For 37 patients, a FDG PET/CT performed in clinical settings was available. In each joint with an abnormal uptake, the maximum standardized uptake value (SUVmax) was estimated.
  
  
  RESULTS
  A total of 260 musculoskeletal foci of ¹⁸F-FPRGD₂ uptake were detected. Most common sites of uptake were joints and discs (n = 160; 61.5%), entheses (osteotendinous and osteoligamentous junctions; n = 55; 21.2%) and recent fractures (n = 18; 6.9%). In addition, 27 (10.4%) miscellaneous foci were detected. Out of the 146 lesions for which a FDG PET was available, 63% showed both ¹⁸F-FPRGD₂ and FDG uptake, 33.6% did not show FDG avidity and 3.4% showed only FDG uptake. The uptake intensity of the 92 lesions positive with ¹⁸F-FPRGD₂ and FDG was similar with both radiopharmaceuticals, but the target-to-background (blood pool or muscle) ratios were significantly higher with ¹⁸F-FPRGD₂ than with FDG (p < 0.0001).
  
  
  CONCLUSIONS
  The ¹⁸F-FPRGD₂ uptake in joints, spine degenerative diseases and tendons was highly prevalent in our population. Up to one-third of ¹⁸F-FPRGD₂ foci showed no FDG uptake suggesting that ¹⁸F-FPRGD₂ signal may not be related to inflammatory angiogenesis only.
authors.affiliation: Division of Nuclear Medicine and Oncological Imaging, Department of Medical Physics, CHU Liege, Liege, Belgium. nwithofs@chu.ulg.ac.be.
authors.forename: Nadia
authors.initials: N
authors.lastname: Withofs
authors.affiliation: Department and Laboratory of Rheumatology CHU Liege and GIGA-Research, University of Liege, Liege, Belgium.
authors.forename: Edith
authors.initials: E
authors.lastname: Charlier
authors.affiliation: Division of Diagnostic Imaging, Department of Medical Physics, CHU Liege, Liege, Belgium.
authors.forename: Paolo
authors.initials: P
authors.lastname: Simoni
authors.affiliation: Division of Diagnostic Imaging, Department of Medical Physics, CHU Liege, Liege, Belgium.
authors.forename: Victoria
authors.initials: V
authors.lastname: Alvarez-Miezentseva
authors.affiliation: Cyclotron Research Centre, University of Liege, Liege, Belgium.
authors.forename: Frédéric
authors.initials: F
authors.lastname: Mievis
authors.affiliation: Cyclotron Research Centre, University of Liege, Liege, Belgium.
authors.forename: Fabrice
authors.initials: F
authors.lastname: Giacomelli
authors.affiliation: Cyclotron Research Centre, University of Liege, Liege, Belgium.
authors.forename: Christine
authors.initials: C
authors.lastname: Mella
authors.affiliation: Department of Radiology, Molecular Imaging Program at Stanford (MIPS), Stanford University, Stanford, CA, USA.
authors.forename: Sanjiv S
authors.initials: SS
authors.lastname: Gambhir
authors.affiliation: Department and Laboratory of Rheumatology CHU Liege and GIGA-Research, University of Liege, Liege, Belgium.
authors.forename: Olivier
authors.initials: O
authors.lastname: Malaise
authors.affiliation: Department and Laboratory of Rheumatology CHU Liege and GIGA-Research, University of Liege, Liege, Belgium.
authors.forename: Dominique
authors.initials: D
authors.lastname: de Seny
authors.affiliation: Department and Laboratory of Rheumatology CHU Liege and GIGA-Research, University of Liege, Liege, Belgium.
authors.forename: Michel
authors.initials: M
authors.lastname: Malaise
authors.affiliation: Division of Nuclear Medicine and Oncological Imaging, Department of Medical Physics, CHU Liege, Liege, Belgium.
authors.forename: Roland
authors.initials: R
authors.lastname: Hustinx
mesh_terms: D000230:Adenocarcinoma / Q000150:complications; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001692:Biological Transport; D002356:Cartilage / Q000378:metabolism; D054337:Cell Dedifferentiation; D019902:Chondrocytes / Q000378:metabolism; D015331:Cohort Studies; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging; D009140:Musculoskeletal Diseases / Q000150:complications / Q000000981:diagnostic imaging* / Q000378:metabolism; D009842:Oligopeptides; D010003:Osteoarthritis / Q000473:pathology; D010456:Peptides, Cyclic; D049268:Positron-Emission Tomography; D011829:Radiation Dosage; D012004:Rectal Neoplasms / Q000150:complications; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed
chemical_list: C000610710:FB-mini-PEG-E(c(RGDyK))2; D009842:Oligopeptides; D010456:Peptides, Cyclic; C047981:arginyl-glycyl-aspartic acid
keywords: Discopathy; Integrin; Joint; Osteoarthritis; PET; RGD