title: Comparison of tumor blood perfusion assessed by dynamic contrast-enhanced MRI with tumor blood supply assessed by invasive imaging.
abstract: OBJECTIVE
  To evaluate the potential of Gd-DTPA-based dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) for providing high-resolution tumor blood perfusion images.
  
  
  METHODS
  Xenografted tumors from two amelanotic human melanoma lines (A-07 and R-18) were used as preclinical models of human cancer. DCE-MRI was performed at a voxel size of 0.5 x 0.2 x 2.0 mm(3) with the use of spoiled gradient recalled sequences. We produced tumor images of E . F (where E is the initial extraction fraction, and F is perfusion) by subjecting the DCE-MRI data to Kety analysis, and then compared those images with images of tumor blood supply. We obtained high-resolution tumor blood supply images using the Bioscope silicon strip detector system to measure the uptake of Na(99m)TcO(4) in histological preparations. We assessed the global blood supply by measuring the tumor uptake of three freely diffusible blood flow tracers: (86)RbCl, [(14)C]IAP, and Na(99m)TcO(4).
  
  
  RESULTS
  E . F was found to mirror the blood supply well in A-07 and R-18 tumors. The mean E . F differed between the A-07 and R-18 tumors by a factor of approximately 1.6, and this difference was similar to the difference in the global blood supply. The intratumor heterogeneity in E . F was significant for tumors of both lines, and this heterogeneity was similar to the intratumor heterogeneity in the blood supply. The intratumor heterogeneity in the blood supply differed slightly between the A-07 and R-18 tumors, and even this difference was mirrored by the E . F images.
  
  
  CONCLUSIONS
  E . F images of xenografted tumors reflect blood perfusion. This implies that E . F may be a useful parameter for improving cancer diagnostics and individualizing cancer treatment. This possibility deserves to be investigated thoroughly in clinical studies.
authors.affiliation: Radiation Biology and Tumor Physiology Group, Department of Radiation Biology and Centre for Research and Training in Radiation Therapy, Norwegian Radium Hospital, Oslo, Norway.
authors.forename: Bjørn A
authors.initials: BA
authors.lastname: Graff
authors.forename: Ilana C
authors.initials: IC
authors.lastname: Benjaminsen
authors.forename: Kjetil G
authors.initials: KG
authors.lastname: Brurberg
authors.forename: Else-Beate M
authors.initials: EB
authors.lastname: Ruud
authors.forename: Einar K
authors.initials: EK
authors.lastname: Rofstad
mesh_terms: D000818:Animals; D003287:Contrast Media / Q000493:pharmacokinetics*; D004195:Disease Models, Animal; D005260:Female; D019786:Gadolinium DTPA / Q000493:pharmacokinetics*; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods*; D018328:Melanoma, Amelanotic / Q000098:blood supply* / Q000503:physiopathology; D008546:Melanoma, Experimental / Q000098:blood supply* / Q000503:physiopathology; D051379:Mice; D008819:Mice, Nude; D009368:Neoplasm Transplantation / Q000379:methods; D012878:Skin Neoplasms / Q000098:blood supply* / Q000503:physiopathology; D013997:Time Factors; D014183:Transplantation, Heterologous
chemical_list: D003287:Contrast Media; D019786:Gadolinium DTPA