title: Diffusion-weighted imaging and dynamic contrast-enhanced MRI of experimental breast cancer bone metastases--a correlation study with histology.
abstract: OBJECTIVE
  To validate imaging parameters from diffusion-weighted imaging and dynamic contrast-enhanced MRI with immunohistology and to non-invasively assess microstructure of experimental breast cancer bone metastases.
  
  
  METHODS
  Animals bearing breast cancer bone metastases were imaged in a clinical 1.5 T MRI scanner. HASTE sequences were performed to calculate apparent diffusion coefficients. Saturation recovery turbo FLASH sequences were conducted while infusing 0.1 mmol/l Gd-DTPA for dynamic contrast-enhanced MRI to quantify parameters amplitude A and exchange rate constant kep. After imaging, bone metastases were analyzed immunohistologically.
  
  
  RESULTS
  We found correlations of the apparent diffusion coefficients from diffusion-weighted imaging with tumor cellularity as assessed with cell nuclei staining. Histological vessel maturity was correlated negatively with parameters A and kep from dynamic contrast-enhanced MRI. Tumor size correlated inversely with cell density and vessel permeability as well as positively with mean vessel calibers. Parameters from the rim of bone metastases differed significantly from values of the center.
  
  
  CONCLUSIONS
  In vivo diffusion-weighted imaging and dynamic contrast-enhanced MRI in experimental bone metastases provide information about tumor cellularity and vascularity and correlate well with immunohistology.
authors: Department of Medical Physics in Radiology, German Cancer Research Center, Im Neuenheimer Feld 280, 69120 Heidelberg, Germany; Department of Hematology, Oncology and Rheumatology, Heidelberg University Hospital, Im Neuenheimer Feld 410, 69120 Heidelberg, Germany.
authors: Maximilian
authors: M
authors: Merz
authors: Department of Medical Physics in Radiology, German Cancer Research Center, Im Neuenheimer Feld 280, 69120 Heidelberg, Germany.
authors: Lisa
authors: L
authors: Seyler
authors: Department of Medical Physics in Radiology, German Cancer Research Center, Im Neuenheimer Feld 280, 69120 Heidelberg, Germany.
authors: Maren
authors: M
authors: Bretschi
authors: Department of Medical Physics in Radiology, German Cancer Research Center, Im Neuenheimer Feld 280, 69120 Heidelberg, Germany.
authors: Wolfhard
authors: W
authors: Semmler
authors: Department of Medical Physics in Radiology, German Cancer Research Center, Im Neuenheimer Feld 280, 69120 Heidelberg, Germany; Institute of Radiology, University Medical Center Erlangen, Palmsanlage 5, 90154 Erlangen, Germany. Electronic address: tobias.baeuerle@uk-erlangen.de.
authors: Tobias
authors: T
authors: Bäuerle
mesh_terms: D000818:Animals; D001859:Bone Neoplasms / Q000175:diagnosis* / Q000556:secondary / Q000648:ultrastructure*; D001943:Breast Neoplasms / Q000473:pathology*; D003287:Contrast Media; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods; D004195:Disease Models, Animal; D019786:Gadolinium DTPA; D007089:Image Enhancement / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D051381:Rats; D011923:Rats, Nude; D015203:Reproducibility of Results
chemical_list: D003287:Contrast Media; D019786:Gadolinium DTPA
keywords: Angiogenesis; Bone metastases; Breast cancer model; Brix model; Diffusion-weighted magnetic resonance imaging; Dynamic contrast-enhanced magnetic resonance imaging