title: Clinical outcome in chordoma: utility of flow cytometry in DNA determination.
abstract: METHODS
  A retrospective review of 100 patients with chordoma of the lumbar spine and sacrum. Twenty-three patients had flow cytometry data available and a minimum follow-up period of 5 years.
  
  
  OBJECTIVE
  To determine whether DNA content and cell cycle analysis were associated with patient outcome.
  
  
  BACKGROUND
  DNA flow cytometry has been shown to be predictive for biologic behavior of various tumors. Chordoma has been evaluated in very small numbers of patients using DNA flow cytometric analysis, and the utility of DNA patterns in predicting outcome has not been clearly demonstrated.
  
  
  METHODS
  Between January 1979 and December 1995, 100 patients underwent surgical resection for chordoma, and 23 had a minimum follow-up period of 5 years with flow cytometry data. DNA content and cell cycle analysis were determined by enzymatically staining cells with propidium iodide dye and passing them through a flow cytometer. DNA histograms were generated. Survivorship and freedom from local recurrence curves were constructed by the Kaplan-Meier method and compared by the log-rank test.
  
  
  RESULTS
  The mean follow-up period was 7.3 years. For this group of 23 patients, mortality was 61% (14 patients) and local recurrence was 78% (18 patients). Eleven patients had tumors with diploid DNA content, and 12 patients had tumors with aneuploid DNA content. Metastases occurred in 4 of the 11 patients with a diploid pattern and 6 of the 12 with an aneuploid pattern. Six of the 11 patients with the diploid pattern died, in comparison with 8 of 12 patients with the aneuploid pattern. The Kaplan-Meier estimated survivorship (95% confidence interval) was 78% (66-90%) at a follow-up period of 5 years and 36% at a follow-up period of 10 years (22-50%), and no significant differences were found between patients with diploid and aneuploid patterns.
  
  
  CONCLUSIONS
  Patients in whom metastases did not develop had a more favorable clinical outcome. DNA pattern was not associated with local recurrence or survival.
authors.affiliation: Department of Orthopaedic Surgery, Mount Sinai Medical Center, San Francisco, USA. BervenS@orthosurg.ucsf.edu
authors.forename: Sigurd
authors.initials: S
authors.lastname: Berven
authors.forename: David
authors.initials: D
authors.lastname: Zurakowski
authors.forename: Henry J
authors.initials: HJ
authors.lastname: Mankin
authors.forename: Mark C
authors.initials: MC
authors.lastname: Gebhardt
authors.forename: Dempsey S
authors.initials: DS
authors.lastname: Springfield
authors.forename: Francis J
authors.initials: FJ
authors.lastname: Hornicek
mesh_terms: D000328:Adult; D000368:Aged; D002453:Cell Cycle; D002817:Chordoma / Q000737:chemistry* / Q000401:mortality* / Q000473:pathology / Q000601:surgery; D004273:DNA, Neoplasm / Q000032:analysis*; D018572:Disease-Free Survival; D005260:Female; D005434:Flow Cytometry; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local; D011003:Ploidies; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D016019:Survival Analysis
chemical_list: D004273:DNA, Neoplasm