title: Multimodality imaging using proton magnetic resonance spectroscopic imaging and18F-fluorodeoxyglucose-positron emission tomography in local prostate cancer.
abstract: OBJECTIVE
  To assess the relationship using multimodality imaging between intermediary citrate/choline metabolism as seen on proton magnetic resonance spectroscopic imaging (1H-MRSI) and glycolysis as observed on18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG-PET/CT) in prostate cancer (PCa) patients.
  
  
  METHODS
  The study included 22 patients with local PCa who were referred for endorectal magnetic resonance imaging/1H-MRSI (April 2002 to July 2007) and18F-FDG-PET/CT and then underwent prostatectomy as primary or salvage treatment. Whole-mount step-section pathology was used as the standard of reference. We assessed the relationships between PET parameters [standardized uptake value (SUVmax and SUVmean)] and MRSI parameters [choline + creatine/citrate (CC/Cmax and CC/Cmean) and total number of suspicious voxels] using spearman's rank correlation, and the relationships of PET and1H-MRSI index lesion parameters to surgical Gleason score.
  
  
  RESULTS
  Abnormal intermediary metabolism on1H-MRSI was present in 21/22 patients, while abnormal glycolysis on18F-FDG-PET/CT was detected in only 3/22 patients. Specifically, index tumor localization rates were 0.95 (95%CI: 0.77-1.00) for1H-MRSI and 0.14 (95%CI: 0.03-0.35) for18F-FDG-PET/CT. Spearman rank correlations indicated little relationship (ρ = -0.36-0.28) between1H-MRSI parameters and18F-FDG-PET/CT parameters. Both the total number of suspicious voxels (ρ = 0.55,P= 0.0099) and the SUVmax (ρ = 0.46,P= 0.0366) correlated weakly with the Gleason score. No significant relationship was found between the CC/Cmax, CC/Cmean or SUVmean and the Gleason score (P= 0.15-0.79).
  
  
  CONCLUSIONS
  The concentration of intermediary metabolites detected by1H MRSI and glycolytic flux measured18F-FDG PET show little correlation. Furthermore, only few tumors were FDG avid on PET, possibly because increased glycolysis represents a late and rather ominous event in the progression of PCa.
authors.affiliation: Amita Shukla-Dave, Heiko Schöder, Yousef Mazaheri, Hedvig Hricak, Department of Radiology, Memorial Sloan-Kettering Cancer Center, New York, NY 10065, United States.
authors.forename: Amita
authors.initials: A
authors.lastname: Shukla-Dave
authors.affiliation: Amita Shukla-Dave, Heiko Schöder, Yousef Mazaheri, Hedvig Hricak, Department of Radiology, Memorial Sloan-Kettering Cancer Center, New York, NY 10065, United States.
authors.forename: Cecilia
authors.initials: C
authors.lastname: Wassberg
authors.affiliation: Amita Shukla-Dave, Heiko Schöder, Yousef Mazaheri, Hedvig Hricak, Department of Radiology, Memorial Sloan-Kettering Cancer Center, New York, NY 10065, United States.
authors.forename: Darko
authors.initials: D
authors.lastname: Pucar
authors.affiliation: Amita Shukla-Dave, Heiko Schöder, Yousef Mazaheri, Hedvig Hricak, Department of Radiology, Memorial Sloan-Kettering Cancer Center, New York, NY 10065, United States.
authors.forename: Heiko
authors.initials: H
authors.lastname: Schöder
authors.affiliation: Amita Shukla-Dave, Heiko Schöder, Yousef Mazaheri, Hedvig Hricak, Department of Radiology, Memorial Sloan-Kettering Cancer Center, New York, NY 10065, United States.
authors.forename: Debra A
authors.initials: DA
authors.lastname: Goldman
authors.affiliation: Amita Shukla-Dave, Heiko Schöder, Yousef Mazaheri, Hedvig Hricak, Department of Radiology, Memorial Sloan-Kettering Cancer Center, New York, NY 10065, United States.
authors.forename: Yousef
authors.initials: Y
authors.lastname: Mazaheri
authors.affiliation: Amita Shukla-Dave, Heiko Schöder, Yousef Mazaheri, Hedvig Hricak, Department of Radiology, Memorial Sloan-Kettering Cancer Center, New York, NY 10065, United States.
authors.forename: Victor E
authors.initials: VE
authors.lastname: Reuter
authors.affiliation: Amita Shukla-Dave, Heiko Schöder, Yousef Mazaheri, Hedvig Hricak, Department of Radiology, Memorial Sloan-Kettering Cancer Center, New York, NY 10065, United States.
authors.forename: James
authors.initials: J
authors.lastname: Eastham
authors.affiliation: Amita Shukla-Dave, Heiko Schöder, Yousef Mazaheri, Hedvig Hricak, Department of Radiology, Memorial Sloan-Kettering Cancer Center, New York, NY 10065, United States.
authors.forename: Peter T
authors.initials: PT
authors.lastname: Scardino
authors.affiliation: Amita Shukla-Dave, Heiko Schöder, Yousef Mazaheri, Hedvig Hricak, Department of Radiology, Memorial Sloan-Kettering Cancer Center, New York, NY 10065, United States.
authors.forename: Hedvig
authors.initials: H
authors.lastname: Hricak
keywords: 18F-fluorodeoxyglucose-positron emission tomography; Prostate cancer; Proton magnetic resonance spectroscopic imaging