title: Feasibility and safety of en bloc resection for primary spine tumors: a systematic review by the Spine Oncology Study Group.
abstract: METHODS
  Systematic review.
  
  
  OBJECTIVE
  To determine the general feasibility and safety of en bloc resection for primary spine tumors by analyzing (1) the effect of incisional biopsy performed before definitive en bloc resection and (2) the rate of achievement of disease-free margins, morbidity, mortality, and health resource utilization.
  
  
  BACKGROUND
  The feasibility of en bloc resection is determined by careful surgical and oncologic staging, and a key step in this process is obtaining a tissue diagnosis. There is currently good evidence to support the premise that the best chance for surgical cure in primary tumors of the spine is by en bloc resection with disease-free margins; however, the early morbidity of these procedures begs the question of whether they are justified.
  
  
  METHODS
  A formal systematic review with search of MEDLINE, EMBASE, and the Cochrane Database of Systematic Reviews databases was undertaken. Included reports described patients with low grade malignant spine tumors, the method of staging and surgical resection, and the complications. Two blinded, independent reviewers used a standardized study selection worksheet.
  
  
  RESULTS
  About 89 articles were identified, with 8 selected after excluding small case series and studies that included other pathologies (e.g., metastatic disease). Weinstein, Boriani, Biagini staging accurately predicted the attainment of wide or marginal en bloc resection in 88% of cases. There was a clear increase in tumor recurrence when intralesional procedures were performed before the definitive en bloc resection. Tumor recurrence significantly shortened patient survival. Surgical complication rates ranged from 13% to 56% and mortality ranged from 0% to 7.7%.
  
  
  CONCLUSIONS
  (1) Incisional biopsy or intralesional resection significantly increases the risk of local recurrence, therefore, transcutaneous computed tomography-guided trocar biopsy is recommended. When there is a suspicion of primary spine tumor, the surgeon who performs the definitive surgery should ideally perform or direct the biopsy procedure. (2) En bloc resection is achievable if staging determines that it is feasible. The adverse event profile of these surgeries is high even at experienced centers. Therefore, experienced, multidisciplinary teams should perform these surgeries. (3) Grade of Recommendation can be "strong recommendation, low-quality evidence."
authors.affiliation: Division of Neurosurgery, University of Saskatchewan, Saskatoon, Saskatchewan, Canada.
authors.forename: Tomasato
authors.initials: T
authors.lastname: Yamazaki
authors.forename: Gregory S
authors.initials: GS
authors.lastname: McLoughlin
authors.forename: Shreyaskuma
authors.initials: S
authors.lastname: Patel
authors.forename: Laurence D
authors.initials: LD
authors.lastname: Rhines
authors.forename: Daryl R
authors.initials: DR
authors.lastname: Fourney
mesh_terms: D001706:Biopsy; D002813:Chondrosarcoma / Q000473:pathology / Q000601:surgery*; D002817:Chordoma / Q000473:pathology / Q000601:surgery*; D006801:Humans; D009364:Neoplasm Recurrence, Local; D013125:Spinal Neoplasms / Q000473:pathology / Q000601:surgery*; D013131:Spine / Q000473:pathology / Q000601:surgery