title: Skull base chondrosarcoma originating from the petroclival junction.
abstract: OBJECTIVE
  To define the presentation of patients with skull base chondrosarcoma, to elucidate surgical strategies, and to identify the role of postoperative radiotherapy.
  
  
  METHODS
  Retrospective review.
  
  
  METHODS
  Tertiary referral center.
  
  
  METHODS
  All patients (n = 33) with skull base chondrosarcoma managed at our institution. The average follow-up time was 7.7 years (range, 0-20 years).
  
  
  METHODS
  Tumor location, presenting symptoms, presence of residual or recurrent tumor, and mortality.
  
  
  RESULTS
  The most common tumor location was the petroclival junction (n = 29). Common presenting symptoms were diplopia (48%) and headache (45%). Surgical approaches included retrosigmoid, transtemporal, transfacial, and frontotemporal craniotomies. Biopsy only was performed in four patients, subtotal resection in 19 patients, and total resection in nine patients. Most patients received postoperative radiotherapy (82%). Follow-up revealed residual, stable disease in 28% of patients and recurrent disease in 24% of patients. The mean time to recurrence was 3.0 +/- 2.8 years. The lack of postoperative radiation was significantly correlated with an increased risk of recurrence (odds ratio, 28; p = 0.007) but incomplete tumor resection was not (p = 0.6). Life-table analysis revealed that the 5-year survival rate was 85% and the 10-year survival rate was 77%. Five patients died; four of the deaths attributable to recurrent disease.
  
  
  CONCLUSIONS
  The characteristic growth pattern of skull base chondrosarcoma is tumor eroding the petroclival junction. Current therapeutic strategy is resection through an extradural subtemporal craniotomy with removal of the petrous apex and clivus. Radical resection of uninvolved structures is often not necessary. Nonetheless, gross total removal is often achievable. Postoperative radiotherapy reduces the chance of tumor recurrence.
authors.affiliation: Department of Otolaryngology, Head and Neck Surgery, University of California, San Francisco, California, USA. jso@bcm.tmc.edu
authors.forename: John S
authors.initials: JS
authors.lastname: Oghalai
authors.forename: James L
authors.initials: JL
authors.lastname: Buxbaum
authors.forename: Robert K
authors.initials: RK
authors.lastname: Jackler
authors.forename: Michael W
authors.initials: MW
authors.lastname: McDermott
mesh_terms: D000328:Adult; D002813:Chondrosarcoma / Q000145:classification / Q000401:mortality* / Q000628:therapy*; D035301:Cranial Fossa, Middle / Q000601:surgery*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009364:Neoplasm Recurrence, Local; D011182:Postoperative Care; D018714:Radiotherapy, Adjuvant; D012189:Retrospective Studies; D019292:Skull Base Neoplasms / Q000145:classification / Q000401:mortality* / Q000628:therapy*; D016019:Survival Analysis; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome