title: Liquid nitrogen or phenolization for giant cell tumor of bone?: a comparative cohort study of various standard treatments at two tertiary referral centers.
abstract: BACKGROUND
  The rate of recurrence of giant cell tumor of bone is decreased by use of adjuvant treatments such as phenol, liquid nitrogen, or polymethylmethacrylate (PMMA) during curettage. We assessed recurrence and complication rates and functional outcome after curettage with use of phenol and PMMA, liquid nitrogen and PMMA, and liquid nitrogen and bone grafts.
  
  
  METHODS
  We retrospectively compared the relative effectiveness of treatment of giant cell tumors of bone at two tertiary centers with a regional function from 1990 to 2010. The 132 (of 201) patients who met the inclusion criteria had a mean age of thirty-three years (range, eleven to sixty-nine years). Treatment assignment depended purely on the center, with primary treatment consisting of curettage with use of phenol and PMMA (n = 82) at one center and with use of either liquid nitrogen and PMMA (n = 26) or liquid nitrogen and bone grafts (n = 24) at the other center. Recurrence and complication rates were determined, and functional outcome was assessed on the basis of the Musculoskeletal Tumor Society (MSTS) score.
  
  
  RESULTS
  The mean duration of follow-up was eight years (range, two to twenty-two years). Recurrence rates were comparable among the groups (28% for phenol and PMMA, 31% for liquid nitrogen and PMMA, and 38% for liquid nitrogen and bone grafts; p = 0.52). Soft-tissue extension increased the recurrence risk (hazard ratio [HR] = 2.1, 95% confidence interval [CI] = 1.1 to 4.0, p = 0.024). The complication rate was 33% after use of liquid nitrogen and bone grafts, 27% after liquid nitrogen and PMMA, and 11% after phenol and PMMA (p = 0.019); complications included osteoarthritis, infection, postoperative fracture, nonunion, transient nerve palsy, and PMMA leakage. The complication risk was increased by the presence of a pathologic fracture (HR = 4.1, 95% CI = 1.7 to 9.5, p = 0.001) and use of liquid nitrogen (HR = 3.9, 95% CI = 1.5 to 10, p = 0.006 for liquid nitrogen and bone grafts; HR = 3.1, 95% CI = 1.1 to 8.6, p = 0.028 for liquid nitrogen and PMMA). The mean MSTS score was 26 (range, 8 to 30) and was comparable among all three groups (p = 0.52).
  
  
  CONCLUSIONS
  Recurrence rates were comparable for treatment with phenol and PMMA, liquid nitrogen and PMMA, and liquid nitrogen and bone grafts. Complication rates were higher after use of liquid nitrogen. The functional outcome was excellent in all three cohorts.
authors.affiliation: Department of Orthopedic Surgery, Leiden University Medical Center, Postzone J11-R70, PO Box 9600, 2300 RC Leiden, The Netherlands. E-mail address for L. van der Heijden: lvanderheijden@lumc.nl.
authors.forename: Lizz
authors.initials: L
authors.lastname: van der Heijden
authors.affiliation: Department of Orthopedic Surgery, Radboud University Medical Center, Postzone 357, PO Box 9101, 6505 HB Nijmegen, The Netherlands.
authors.forename: Ingrid C M
authors.initials: IC
authors.lastname: van der Geest
authors.affiliation: Department of Orthopedic Surgery, Radboud University Medical Center, Postzone 357, PO Box 9101, 6505 HB Nijmegen, The Netherlands.
authors.forename: H W Bart
authors.initials: HW
authors.lastname: Schreuder
authors.affiliation: Department of Orthopedic Surgery, Leiden University Medical Center, Postzone J11-R70, PO Box 9600, 2300 RC Leiden, The Netherlands. E-mail address for L. van der Heijden: lvanderheijden@lumc.nl.
authors.forename: Michiel A J
authors.initials: MA
authors.lastname: van de Sande
authors.affiliation: Department of Orthopedic Surgery, Leiden University Medical Center, Postzone J11-R70, PO Box 9600, 2300 RC Leiden, The Netherlands. E-mail address for L. van der Heijden: lvanderheijden@lumc.nl.
authors.forename: P D Sander
authors.initials: PD
authors.lastname: Dijkstra
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001859:Bone Neoplasms / Q000628:therapy*; D016025:Bone Transplantation; D002648:Child; D015331:Cohort Studies; D003475:Curettage; D005260:Female; D018212:Giant Cell Tumor of Bone / Q000628:therapy*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009584:Nitrogen / Q000627:therapeutic use*; D019800:Phenol / Q000627:therapeutic use*; D019904:Polymethyl Methacrylate / Q000627:therapeutic use*; D012189:Retrospective Studies; D062606:Tertiary Care Centers; D055815:Young Adult
chemical_list: D019800:Phenol; D019904:Polymethyl Methacrylate; D009584:Nitrogen