title: Transition zone prostate cancer: metabolic characteristics at 1H MR spectroscopic imaging--initial results.
abstract: OBJECTIVE
  To determine whether cancers of the prostate transition zone (TZ) possess a unique metabolic pattern by which they may be identified at proton magnetic resonance (MR) spectroscopic imaging.
  
  
  METHODS
  Findings in 40 patients who underwent combined endorectal MR imaging and hydrogen 1 MR spectroscopic imaging before radical prostatectomy and who had TZ tumor identified subsequently at step-section pathologic analysis were retrospectively reviewed. Within this population, a subset of 16 patients whose TZ tumor had a largest diameter of 1 cm or greater and was included in the MR spectroscopic imaging excitation volume was identified. In these 16 patients, the ratios of choline-containing compounds (Cho) and creatine/phosphocreatine (Cr) to citrate (Cit) (ie, [Cho + Cr]/Cit), Cho/Cr, and Cho/Cit were compared in tumor and control tissues. The presence of only Cho and the absence of all metabolites were also assessed.
  
  
  RESULTS
  The mean values of (Cho + Cr)/Cit, Cho/Cr, and Cho/Cit were different between TZ cancer and control tissues (P =.001, P =.003, and P =.001, respectively; Wilcoxon signed rank test). Nine (56%) of 16 patients had at least one tumor voxel in which Cho comprised the only detectable peak, while no control voxels showed only Cho (P =.008, McNemar test). The percentage of voxels in which no metabolites were detected did not differ between tumor and control tissues (P =.134, McNemar test).
  
  
  CONCLUSIONS
  TZ cancer has a metabolic profile that is different from that of benign TZ tissue; however, the broad range of metabolite ratios observed in TZ cancer precludes the use of a single ratio to differentiate TZ cancer from benign TZ tissue.
authors.affiliation: Departments of Medical Physics, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 10021, USA. zakiank@mskcc.org
authors.forename: Kristen L
authors.initials: KL
authors.lastname: Zakian
authors.forename: Steven
authors.initials: S
authors.lastname: Eberhardt
authors.forename: Hedvig
authors.initials: H
authors.lastname: Hricak
authors.forename: Amita
authors.initials: A
authors.lastname: Shukla-Dave
authors.forename: Shanon
authors.initials: S
authors.lastname: Kleinman
authors.forename: Manickam
authors.initials: M
authors.lastname: Muruganandham
authors.forename: Kanishka
authors.initials: K
authors.lastname: Sircar
authors.forename: Michael W
authors.initials: MW
authors.lastname: Kattan
authors.forename: Victor E
authors.initials: VE
authors.lastname: Reuter
authors.forename: Peter T
authors.initials: PT
authors.lastname: Scardino
authors.forename: Jason A
authors.initials: JA
authors.lastname: Koutcher
mesh_terms: D002794:Choline / Q000032:analysis; D019343:Citric Acid / Q000032:analysis; D003401:Creatine / Q000032:analysis; D006801:Humans; D008279:Magnetic Resonance Imaging; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D008875:Middle Aged; D010725:Phosphocreatine / Q000032:analysis; D011467:Prostate / Q000737:chemistry / Q000473:pathology; D011471:Prostatic Neoplasms / Q000737:chemistry / Q000175:diagnosis* / Q000473:pathology; D012189:Retrospective Studies
chemical_list: D010725:Phosphocreatine; D019343:Citric Acid; D003401:Creatine; D002794:Choline