title: Detection and quantification of breast tumor necrosis with MR imaging: value of the necrosis-avid contrast agent Gadophrin-3.
abstract: OBJECTIVE
  The authors evaluated the use of T1-weighted magnetic resonance (MR) imaging with Gadophrin-3 enhancement and of plain T2-weighted MR imaging to detect and quantify breast tumor necrosis.
  
  
  METHODS
  Twenty EMT-6 tumors (mouse mammary sarcoma), implanted into the mammary fat pad of BALB/c-AnNCrl mice, underwent MR imaging with plain T2-weighted and T1-weighted fast field echo sequences before and 24 hours after injection of Gadophrin-3, a new necrosis-avid contrast agent. Tumor necrosis on MR images was quantified by means of a dedicated segmentation program and was correlated with histologic findings.
  
  
  RESULTS
  In all tumors a central necrosis was revealed by histopathologic analysis, and central enhancement was seen with Gadophrin-3 on T1-weighted images. Small tumors (diameter, < 1 cm) showed an inhomogeneous central enhancement, whereas larger tumors (diameter, > 1 cm) enhanced mainly in the periphery of necrotic tissue. Plain T2-weighted images showed a hyperintense central area in only three of 20 cases with a large central necrosis.
  
  
  CONCLUSIONS
  Gadophrin-3-enhanced T1-weighted images are superior to plain T2-weighted images for the detection of necrosis in a murine tumor xenograft model.
authors.affiliation: Department of Radiology, Technical University, Ismaninger Strasse 22, 81675 Munich, Germany.
authors.forename: Stephan
authors.initials: S
authors.lastname: Metz
authors.forename: Heike E
authors.initials: HE
authors.lastname: Daldrup-Unk
authors.forename: Thomas
authors.initials: T
authors.lastname: Richter
authors.forename: Christoph
authors.initials: C
authors.lastname: Räth
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Ebert
authors.forename: Marcus
authors.initials: M
authors.lastname: Settles
authors.forename: Ernst J
authors.initials: EJ
authors.lastname: Rummeny
authors.forename: Thomas M
authors.initials: TM
authors.lastname: Link
authors.forename: Morand
authors.initials: M
authors.lastname: Piert
mesh_terms: D000818:Animals; D003287:Contrast Media; D005260:Female; D019786:Gadolinium DTPA; D008279:Magnetic Resonance Imaging; D008325:Mammary Neoplasms, Experimental / Q000473:pathology*; D008665:Metalloporphyrins; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D009336:Necrosis; D009368:Neoplasm Transplantation; D012513:Sarcoma, Experimental / Q000473:pathology
chemical_list: D003287:Contrast Media; C476926:Gadophrin-3; D008665:Metalloporphyrins; D019786:Gadolinium DTPA