title: CT and MR findings in a neuroforaminal extraskeletal Ewing sarcoma mimicking benign nerve sheath tumor.
abstract: BACKGROUND
  We report the CT and MR findings in a 30-year-old man with extraskeletal Ewing sarcoma (EES) involving the left neural foramen at L5-S1 level.
  
  
  METHODS
  The patient was evaluated with preoperative lumbosacral CT and MR imaging and postoperative lumbosacral MR imaging.
  
  
  RESULTS
  The lesion was hyperdense on CT, isointense on T1- and T2-weighted MR images, and enhanced homogeneously after intravenous gadolinium injection. With these CT and MR findings, surgery was performed with a presumptive diagnosis of nerve sheath tumor, but the histopathological examination revealed EES. Chemotherapy and radiotherapy were planned postoperatively.
  
  
  CONCLUSIONS
  This case illustrates that even in benign looking lesions in a neuroforamen one can never exclude malignancy, and this is even more true in a population of young adults.
authors.affiliation: Department of Radiology, AZ Sint-Lucas Hospital, Ghent, Belgium. serhatavcu@hotmail.com
authors.forename: S
authors.initials: S
authors.lastname: Avcu
authors.forename: H N
authors.initials: HN
authors.lastname: Ozcan
authors.forename: M
authors.initials: M
authors.lastname: Izmirli
authors.forename: M
authors.initials: M
authors.lastname: Lemmerling
mesh_terms: D000328:Adult; D003937:Diagnosis, Differential; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D018317:Nerve Sheath Neoplasms / Q000175:diagnosis*; D012512:Sarcoma, Ewing / Q000175:diagnosis* / Q000601:surgery; D013125:Spinal Neoplasms / Q000175:diagnosis* / Q000601:surgery; D014057:Tomography, X-Ray Computed