title: Comparison of [(18)F]DCFPyL and [ (68)Ga]Ga-PSMA-HBED-CC for PSMA-PET Imaging in Patients with Relapsed Prostate Cancer.
abstract: OBJECTIVE
  Gallium-68 (Ga-68)-labeled tracers for imaging expression of the prostate-specific membrane antigen (PSMA) such as the [(68)Ga]Ga-PSMA-HBED-CC have already demonstrated high potential for the detection of recurrent prostate cancer. However, compared to Ga-68, a labeling with fluorine-18 (F-18) would offer advantages with respect to availability, production amount, and image resolution. [(18)F]DCFPyL is a promising F-18-labeled candidate for PSMA-positron emission tomography (PET) imaging that has been recently introduced. In the current study, we aimed to compare [(68)Ga]Ga-PSMA-HBED-CC and [(18)F]DCFPyL for clinical use in biochemically relapsed prostate cancer.
  
  
  METHODS
  In 14 selected patients with PSA relapse of prostate cancer, [(18)F]DCFPyL PET/X-ray computed tomography (CT) was performed in addition to [(68)Ga]Ga-PSMA-HBED-CC PET/CT. A systematic comparison was carried out between results obtained with both tracers with regard to the number of detected PSMA-positive lesions, the standardized uptake value (SUV)max and the lesion to background ratios.
  
  
  RESULTS
  All suspicious lesions identified by [(68)Ga]Ga-PSMA-HBED-CC were also detected with [(18)F]DCFPyL. In three patients, additional lesions were observed using [(18)F]DCFPyL PET/CT. The mean SUVmax in the concordant [(18)F]DCFPyL PSMA-positive lesions was significantly higher as compared to [(68)Ga]Ga-PSMA-HBED-CC (14.5 vs. 12.2, p = 0.028, n = 15). The mean tumor to background ratios (n = 15) were significantly higher for [(18)F]DCFPyL compared to [(68)Ga]Ga-PSMA-HBED-CC using kidney, spleen, or parotid as reference organs (p = 0.006, p = 0.002, p = 0.008), but no significant differences were found using the liver (p = 0.167) or the mediastinum (p = 0.363) as reference organs.
  
  
  CONCLUSIONS
  [(18)F]DCFPyL PET/CT provided a high image quality and visualized small prostate lesions with excellent sensitivity. [(18)F]DCFPyL represents a highly promising alternative to [(68)Ga]Ga-PSMA-HBED-CC for PSMA-PET/CT imaging in relapsed prostate cancer.
authors.affiliation: Department of Nuclear Medicine, University Hospital of Cologne, Kerpener Str. 62, 50937, Cologne, Germany, markus.dietlein@uk-koeln.de.
authors.forename: Markus
authors.initials: M
authors.lastname: Dietlein
authors.forename: Carsten
authors.initials: C
authors.lastname: Kobe
authors.forename: Georg
authors.initials: G
authors.lastname: Kuhnert
authors.forename: Simone
authors.initials: S
authors.lastname: Stockter
authors.forename: Thomas
authors.initials: T
authors.lastname: Fischer
authors.forename: Klaus
authors.initials: K
authors.lastname: Schomäcker
authors.forename: Matthias
authors.initials: M
authors.lastname: Schmidt
authors.forename: Felix
authors.initials: F
authors.lastname: Dietlein
authors.forename: Boris D
authors.initials: BD
authors.lastname: Zlatopolskiy
authors.forename: Philipp
authors.initials: P
authors.lastname: Krapf
authors.forename: Raphael
authors.initials: R
authors.lastname: Richarz
authors.forename: Stephan
authors.initials: S
authors.lastname: Neubauer
authors.forename: Alexander
authors.initials: A
authors.lastname: Drzezga
authors.forename: Bernd
authors.initials: B
authors.lastname: Neumaier
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D004492:Edetic Acid / Q000031:analogs & derivatives* / Q000493:pharmacokinetics / Q000627:therapeutic use; D005709:Gallium Isotopes; D005710:Gallium Radioisotopes; D006801:Humans; D008099:Liver / Q000378:metabolism; D008239:Lysine / Q000031:analogs & derivatives* / Q000493:pharmacokinetics / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D009842:Oligopeptides / Q000493:pharmacokinetics / Q000627:therapeutic use*; D049268:Positron-Emission Tomography / Q000379:methods*; D011471:Prostatic Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D019275:Radiopharmaceuticals / Q000493:pharmacokinetics / Q000627:therapeutic use*; D012008:Recurrence; D014508:Urea / Q000031:analogs & derivatives* / Q000493:pharmacokinetics / Q000627:therapeutic use
chemical_list: C572626:2-(3-(1-carboxy-5-((6-fluoropyridine-3-carbonyl)amino)pentyl)ureido)pentanedioic acid; D005709:Gallium Isotopes; D005710:Gallium Radioisotopes; D009842:Oligopeptides; D019275:Radiopharmaceuticals; C000718244:gallium 68 PSMA-11; D014508:Urea; D004492:Edetic Acid; D008239:Lysine