title: The choice of region of interest measures in contrast-enhanced magnetic resonance image characterization of experimental breast tumors.
abstract: OBJECTIVE
  The objectives of this study were to determine if magnetic resonance (MR) estimates of quantitative tissue microvascular characteristics from regions of interest (ROI) limited to the tumor periphery provided a better correlation with tumor histologic grade than ROI defined for the whole tumor in cross-section.
  
  
  METHODS
  A metaanalysis was based on 98 quantitative MR image breast tumor characterizations acquired in 3 separate experimental studies using identical methods for tumor induction and contrast enhancement.
  
  
  RESULTS
  The endothelial transfer coefficient (K) of albumin (Gd-DTPA)30 from the tumor periphery correlated (r = 0.784) significantly more strongly (P < 0.001) with the pathologic tumor grade than K derived from the whole tumor (r = 0.604). K estimates, either from the tumor periphery or from the whole tumor, correlated significantly more strongly with histologic grade (P < 0.01) than MR image estimates of fractional plasma volume (fPV) from either tumor periphery (r = 0.368) or whole tumor (r = 0.323).
  
  
  CONCLUSIONS
  K estimates from the tumor periphery were the best of these measurable MR image microvascular characteristics for predicting the histologic grade.
authors.affiliation: Center for Pharmaceutical and Molecular Imaging, Department of Radiology, University of California San Francisco, CA 94143, USA.
authors.forename: Anda
authors.initials: A
authors.lastname: Preda
authors.forename: Karl
authors.initials: K
authors.lastname: Turetschek
authors.forename: Heike
authors.initials: H
authors.lastname: Daldrup
authors.forename: Eugenia
authors.initials: E
authors.lastname: Floyd
authors.forename: Viktor
authors.initials: V
authors.lastname: Novikov
authors.forename: David M
authors.initials: DM
authors.lastname: Shames
authors.forename: Timothy P L
authors.initials: TP
authors.lastname: Roberts
authors.forename: Wayne O
authors.initials: WO
authors.lastname: Carter
authors.forename: Robert C
authors.initials: RC
authors.lastname: Brasch
mesh_terms: D000818:Animals; D003287:Contrast Media; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008325:Mammary Neoplasms, Experimental / Q000175:diagnosis*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012189:Retrospective Studies
chemical_list: D003287:Contrast Media