title: Dysprosium-enhanced MR imaging for tumor tissue characterization. An experimental study in a human xenograft model.
abstract: OBJECTIVE
  To evaluate dysprosium-enhanced MR imaging for differentiation between morphologically intact and necrotic tumor tissue in a tumor model.
  
  
  METHODS
  A human colon carcinoma was transplanted subcutaneously into 9 nude (immunodeprived) rats. MR imaging was performed before and after injection of the dysprosium agent Dy-DTPA-BMA. T1-, T2- and T2*-weighted sequences were acquired. The tumors were dissected, histological sections were prepared, and compared with corresponding MR images.
  
  
  RESULTS
  In intact tissue, the MR signal intensity in the T2- and T2*-weighted images decreased after Dy injection and the delineation of the intact regions were sharp and corresponded well to the gross histological sections.
  
  
  CONCLUSIONS
  Dy-enhanced MR imaging facilitated the differentiation between intact and necrotic tumor tissue.
authors.affiliation: Department of Diagnostic Radiology, University Hospital, Uppsala University, Sweden.
authors.forename: C
authors.initials: C
authors.lastname: Wang
authors.forename: A
authors.initials: A
authors.lastname: Sundin
authors.forename: A
authors.initials: A
authors.lastname: Ericsson
authors.forename: T
authors.initials: T
authors.lastname: Bach-Gansmo
authors.forename: A
authors.initials: A
authors.lastname: Hemmingsson
authors.forename: H
authors.initials: H
authors.lastname: Ahlström
mesh_terms: D000230:Adenocarcinoma / Q000175:diagnosis; D000818:Animals; D003110:Colonic Neoplasms / Q000175:diagnosis*; D003287:Contrast Media; D004419:Dysprosium; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D009336:Necrosis; D009368:Neoplasm Transplantation; D051381:Rats; D011923:Rats, Nude; D014183:Transplantation, Heterologous
chemical_list: D003287:Contrast Media; D004419:Dysprosium