title: Male sex as a risk factor for the clinical course of skull base chordomas.
abstract: OBJECTIVE
  Chordomas of the skull base are rare and locally invasive and have a poor prognosis. The aim of this retrospective multicenter study was to evaluate the current pattern of care and clinical course and to identify prognostic factors.
  
  
  METHODS
  A total of 47 patients (26 men; mean age 48.5 years) treated in 5 centers were included. Histology was centrally reviewed; additionally, semiquantitative N- and E-cadherin expression analysis was performed. Prognostic factors were obtained from multivariate regression models. For survival analysis the Kaplan-Meier method was used.
  
  
  RESULTS
  The median follow-up period was 5.2 years. Complete resection, incomplete resection, and extended biopsy were performed in 14.9%, 80.9%, and 4.3% of patients, respectively. Surgical morbidity was not associated with extent of resection. Adjuvant radiation therapy was performed in 30 (63.8%) of 47 patients. The median progression-free survival (PFS) was 7.3 years. Complete resection prolonged median overall survival (OS) (p = 0.04). Male patients presented with worse PFS (4.8 years vs 9.8 years; p = 0.04) and OS (8.3 years vs not reached; p = 0.03) even though complete resection was exclusively achieved in the male subpopulation. Multivariate analysis confirmed male sex as the most important risk factor for tumor progression (p = 0.04) and death (p = 0.02). Age, duration of symptoms, initial Karnofsky Performance Scale score, brainstem compression, involvement of the petrous bone, infiltration of the dura mater, modality and dose of radiation therapy, and the E- and N-cadherin expression patterns did not gain prognostic relevance.
  
  
  CONCLUSIONS
  In skull base chordomas, male patients bear a higher risk of progressive disease and death. Male patients might benefit from more aggressive adjuvant therapy and/or from a closer follow-up schedule.
authors.affiliation: Department of Neurosurgery and.
authors.forename: Walter
authors.initials: W
authors.lastname: Rachinger
authors.forename: Sabina
authors.initials: S
authors.lastname: Eigenbrod
authors.forename: Stephan
authors.initials: S
authors.lastname: Dützmann
authors.forename: Matthias
authors.initials: M
authors.lastname: Simon
authors.forename: Guenther C
authors.initials: GC
authors.lastname: Feigl
authors.forename: Natalia
authors.initials: N
authors.lastname: Kremenevskaja
authors.forename: Hans
authors.initials: H
authors.lastname: Kretzschmar
authors.forename: Stefan
authors.initials: S
authors.lastname: Zausinger
authors.forename: Friedrich-Wilhelm
authors.initials: FW
authors.lastname: Kreth
authors.forename: Niklas
authors.initials: N
authors.lastname: Thon
authors.forename: Jörg-Christian
authors.initials: JC
authors.lastname: Tonn
mesh_terms: D001706:Biopsy; D002817:Chordoma / Q000453:epidemiology* / Q000401:mortality* / Q000473:pathology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D053208:Kaplan-Meier Estimate; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D012044:Regression Analysis; D012189:Retrospective Studies; D012307:Risk Factors; D012737:Sex Factors; D019292:Skull Base Neoplasms / Q000453:epidemiology* / Q000401:mortality* / Q000473:pathology; D015996:Survival Rate
keywords: KPS = Karnofsky Performance Scale; OS = overall survival; PBRT = proton beam radiotherapy; PFS = progression-free survival; cadherin; chordoma; prognostic factors; sex; skull base