title: Prostate cancer tumor grade differentiation with dynamic contrast-enhanced MR imaging in the rat: comparison of macromolecular and small-molecular contrast media--preliminary experience.
abstract: OBJECTIVE
  To differentiate prostate cancers of different histopathologic grades with dynamic gadolinium-enhanced magnetic resonance (MR) imaging. Results with a conventional small-molecular contrast medium (CM) were compared to those with a prototypic macromolecular CM.
  
  
  METHODS
  High- and low-grade tumors, sublines of the Dunning R3327 rat prostate cancer line, were subcutaneously implanted into the flanks of 12 male Copenhagen rats. Dynamic contrast material-enhanced MR imaging was performed with small-molecular CM and macromolecular CM at an interval of 1 day. Microvascular permeability, as estimated with the endothelial transfer coefficient, and fractional plasma volume were calculated for each tumor and each CM by means of a two-compartmental, bidirectional kinetic model.
  
  
  RESULTS
  Mean endothelial transfer coefficient values for both macromolecular CM and small-molecular CM were significantly different between the two tumor sublines (P = .0004 and P = .01, respectively). For the high- and low-grade tumors, no overlap of values was seen with macromolecular CM, but a broad overlap was seen with small-molecular CM despite a significant difference in mean values.
  
  
  CONCLUSIONS
  Dynamic contrast-enhanced MR imaging permits differentiation of histopathologic prostatic tumor types. Quantitative microvascular permeability characteristics estimated from macromolecular CM-enhanced data were significantly superior to those derived from small-molecular CM-enhanced data.
authors.affiliation: Department of Radiology, University of California, San Francisco 94143-0628, USA.
authors.forename: A
authors.initials: A
authors.lastname: Gossmann
authors.forename: Y
authors.initials: Y
authors.lastname: Okuhata
authors.forename: D M
authors.initials: DM
authors.lastname: Shames
authors.forename: T H
authors.initials: TH
authors.lastname: Helbich
authors.forename: T P
authors.initials: TP
authors.lastname: Roberts
authors.forename: M F
authors.initials: MF
authors.lastname: Wendland
authors.forename: S
authors.initials: S
authors.lastname: Huber
authors.forename: R C
authors.initials: RC
authors.lastname: Brasch
mesh_terms: D000230:Adenocarcinoma / Q000175:diagnosis / Q000473:pathology; D000418:Albumins; D000818:Animals; D002199:Capillary Permeability; D002277:Carcinoma / Q000175:diagnosis / Q000473:pathology; D003287:Contrast Media / Q000493:pharmacokinetics; D019786:Gadolinium DTPA / Q000493:pharmacokinetics; D008279:Magnetic Resonance Imaging; D008297:Male; D008970:Molecular Weight; D009368:Neoplasm Transplantation; D011471:Prostatic Neoplasms / Q000175:diagnosis / Q000473:pathology*; D051381:Rats
chemical_list: D000418:Albumins; D003287:Contrast Media; C058946:albumin-(gadolinium-DTPA); D019786:Gadolinium DTPA