title: Radiosurgery for chordomas and chondrosarcomas of the skull base.
abstract: OBJECTIVE
  Chordomas and chondrosarcomas of the skull base are aggressive and locally destructive tumors with a high tendency for local progression despite treatment. The authors evaluated the effect of stereotactic radiosurgery (SRS) on local tumor control and survival.
  
  
  METHODS
  Twenty-eight patients with histologically confirmed chordomas (18) or chondrosarcomas (10) underwent Gamma Knife SRS either as primary or adjuvant treatment. Their ages ranged from 17 to 72 years (median 44 years). The most common presenting symptom was diplopia (26 patients, 93%). In two patients, SRS was the sole treatment. Twenty-six patients underwent between one and five additional surgical procedures. Two underwent an initial transsphenoidal biopsy. The average tumor volume was 9.8 cm3. The median dose to the tumor margin was 16 Gy.
  
  
  RESULTS
  No patient was lost to follow-up. Transient symptomatic adverse radiation effects developed in only one patient. The actuarial local tumor control for chondrosarcomas at 5 years was 80 +/- 10.1%. For chordomas both the actuarial tumor control and survival was 62.9 +/- 10.4%.
  
  
  CONCLUSIONS
  Stereotactic radiosurgery is an important option for skull base chordomas and chondrosarcomas either as primary or adjunctive treatment. Multimodal management appears crucial to improve tumor control in most patients.
authors.affiliation: Department of Neurological Surgery, University of Pittsburgh School of Medicine and University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA.
authors.forename: Juan J
authors.initials: JJ
authors.lastname: Martin
authors.forename: Ajay
authors.initials: A
authors.lastname: Niranjan
authors.forename: Douglas
authors.initials: D
authors.lastname: Kondziolka
authors.forename: John C
authors.initials: JC
authors.lastname: Flickinger
authors.forename: Karl A
authors.initials: KA
authors.lastname: Lozanne
authors.forename: L Dade
authors.initials: LD
authors.lastname: Lunsford
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001706:Biopsy; D002813:Chondrosarcoma / Q000401:mortality / Q000473:pathology / Q000601:surgery*; D002817:Chordoma / Q000401:mortality / Q000473:pathology / Q000601:surgery*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009017:Morbidity; D011829:Radiation Dosage; D016634:Radiosurgery / Q000009:adverse effects / Q000401:mortality; D019292:Skull Base Neoplasms / Q000401:mortality / Q000473:pathology / Q000601:surgery*; D015996:Survival Rate; D016896:Treatment Outcome