title: Primary Extradural Tumors of the Spine - Case Review with Evidence-guided Management.
abstract: BACKGROUND
  Primary extradural tumors of the spine comprise only a small percentage of all spinal tumors. However, given their relative radioresistance and their typical malignant, invasive nature, surgery may be associated with fairly high morbidity and mortality rates. Furthermore, it may be especially difficult to achieve gross total resections with tumor-free margins.
  
  
  METHODS
  We present two cases and review the literature regarding the presentation, diagnosis, and evidence-based guidance/treatment of primary extradural spinal tumors. The first patient with an L1 chordoma presented with cauda equina syndrome. Following surgery, the second patient, with a giant cell tumor of the cervicothoracic junction, responded well to the novel drug denosumab, a monoclonal antibody to the RANK ligand.
  
  
  CONCLUSIONS
  Primary extradural spine tumors pose significant challenges to surgeons as the aim is to achieve satisfactory surgical outcomes with clean tumor margins (e.g, thus avoid recurrence) while minimizing morbidity. Improvements in radiotherapy, chemotherapy, and novel molecular drugs may increase survival rates and improve overall outcomes.
authors.affiliation: Department of Neurosurgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA.
authors.forename: Fred C
authors.initials: FC
authors.lastname: Lam
authors.affiliation: Department of Neurosurgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA.
authors.forename: Jeffrey E
authors.initials: JE
authors.lastname: Arle
authors.affiliation: Department of Orthopaedics, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA.
authors.forename: Paul A
authors.initials: PA
authors.lastname: Glazer
authors.affiliation: Department of Neurosurgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA.
authors.forename: Ekkehard M
authors.initials: EM
authors.lastname: Kasper
keywords: Chemotherapy; extradural; malignant; molecular drug treatments; primary; radiotherapy; spine; tumors