title: Mesenchymal extraskeletal chondrosarcoma of the orbit. Report of a case and review of the literature.
abstract: BACKGROUND
  Extraskeletal mesenchymal chondrosarcoma (MCS) is relatively uncommon. Orbital location is extremely rare: only 16 cases have been reported until now. We report a case of extraskeletal mesenchymal chondrosarcoma in a 27-year-old man and review the literature on its manifestations and management.
  
  
  METHODS
  This patient had a 2-year history of progressive proptosis of the right eye. Skull X-ray and CT scan showed intraorbital calcification and a large lesion in the upper right orbit. He was operated three times because of recurrence of the tumor. The last recurrence was observed to have extension to the intracranial region, detected on MRI and CT scan. This secondary extension of the tumor to the intracranial region has not been previously reported. Immunohistochemical analysis for S-100 protein showed focal positivity.
  
  
  CONCLUSIONS
  Mesenchymal chondrosarcoma of the orbit is rare, and secondary extension to the intracranial region has not previously been reported.
authors.affiliation: Service de Neurochirurgie, Institut National de Neurologie, Tunis, Tunisie.
authors.forename: N
authors.initials: N
authors.lastname: Khouja
authors.forename: S
authors.initials: S
authors.lastname: Ben Amor
authors.forename: H
authors.initials: H
authors.lastname: Jemel
authors.forename: N
authors.initials: N
authors.lastname: Kchir
authors.forename: H
authors.initials: H
authors.lastname: Boussen
authors.forename: M
authors.initials: M
authors.lastname: Khaldi
mesh_terms: D000328:Adult; D018211:Chondrosarcoma, Mesenchymal / Q000175:diagnosis / Q000601:surgery; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009918:Orbital Neoplasms / Q000175:diagnosis / Q000601:surgery; D014057:Tomography, X-Ray Computed