title: Ewing's sarcoma recurrence vs radiation necrosis in dynamic contrast-enhanced MR imaging: a case report.
abstract: OBJECTIVE
  We report a case of Ewing's sarcoma in the right distal femur in a 6-year-old male to demonstrate how dynamic contrast-enhanced magnetic resonance imaging (DEMRI) findings predicted histopathology.
  
  
  METHODS
  DEMRI was performed at presentation and during and after completion of chemotherapy and radiation therapy. Histopathologic studies were done at presentation, at 77 weeks (20 weeks after a pathological fracture), and from the en bloc resection at 104 weeks.
  
  
  RESULTS
  DEMRI predicted the early tumor response, absence of tumor recurrence, presence of necrosis and lack of fracture healing, confirmed by histopathology.
  
  
  CONCLUSIONS
  DEMRI is a clinically useful tool in managing Ewing's sarcoma.
authors: Department of Diagnostic Imaging, St. Jude Children's Research Hospital, 332 N. Lauderdale, Memphis TN 38105-2794, USA.
authors: A M
authors: AM
authors: El Khadrawy
authors: F A
authors: FA
authors: Hoffer
authors: W E
authors: WE
authors: Reddick
mesh_terms: D002675:Child, Preschool; D003287:Contrast Media; D005264:Femoral Fractures / Q000175:diagnosis; D005266:Femoral Neoplasms / Q000175:diagnosis*; D005269:Femur / Q000473:pathology; D005598:Fractures, Spontaneous / Q000175:diagnosis; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D010025:Osteoradionecrosis / Q000175:diagnosis*; D012512:Sarcoma, Ewing / Q000175:diagnosis* / Q000532:radiotherapy
chemical_list: D003287:Contrast Media