title: Reproducibility and correlation between quantitative and semiquantitative dynamic and intrinsic susceptibility-weighted MRI parameters in the benign and malignant human prostate.
abstract: OBJECTIVE
  To assess the reproducibility of relaxivity- and susceptibility-based dynamic contrast-enhanced magnetic resonance imaging (MRI) in the benign and malignant prostate gland and to correlate the kinetic parameters obtained.
  
  
  METHODS
  Twenty patients with prostate cancer underwent paired scans before and after androgen deprivation therapy. Quantitative parametric maps for T(1)- and T(2)*-weighted parameters were calculated (K(trans), k(ep),v(e), IAUC(60), rBV, rBF, and R(2)*). The reproducibility of and correlation between each parameter were determined using standard methods at both timepoints.
  
  
  RESULTS
  T(1)-derived parameters are more reproducible than T(2)*-weighted measures, both becoming more variable following androgen deprivation (variance coefficients for prostate K(trans) and rBF increased from 13.9%-15.8% and 42.5%-90.8%, respectively). Tumor R(2)* reproducibility improved after androgen ablation (23.3%-11.8%). IAUC(60) correlated strongly with K(trans), v(e), and k(ep) (all P < 0.001). R(2)* did not correlate with other parameters.
  
  
  CONCLUSIONS
  This study is the first to document the variability and repeatability of T(1)- and T(2)*-weighted dynamic MRI and intrinsic susceptibility-weighted MRI for the various regions of the human prostate gland before and after androgen deprivation. These data provide a valuable source of reference for groups that plan to use dynamic contrast-enhanced MRI or intrinsic susceptibility-weighted MRI for the assessment of treatment response in the benign or malignant prostate.
authors.affiliation: Marie Curie Research Wing, Mount Vernon Hospital, Northwood, Middlesex, United Kingdom.
authors.forename: Roberto
authors.initials: R
authors.lastname: Alonzi
authors.forename: N Jane
authors.initials: NJ
authors.lastname: Taylor
authors.forename: J James
authors.initials: JJ
authors.lastname: Stirling
authors.forename: James A
authors.initials: JA
authors.lastname: d'Arcy
authors.forename: David J
authors.initials: DJ
authors.lastname: Collins
authors.forename: Michele I
authors.initials: MI
authors.lastname: Saunders
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Hoskin
authors.forename: Anwar R
authors.initials: AR
authors.lastname: Padhani
mesh_terms: D000368:Aged; D000704:Analysis of Variance; D003287:Contrast Media; D019786:Gadolinium DTPA; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007091:Image Processing, Computer-Assisted / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011467:Prostate / Q000473:pathology; D011469:Prostatic Diseases / Q000175:diagnosis; D011471:Prostatic Neoplasms / Q000175:diagnosis*; D015203:Reproducibility of Results
chemical_list: D003287:Contrast Media; D019786:Gadolinium DTPA