title: Jugulotympanic paragangliomas treated with Gamma Knife radiosurgery: a single-center review of 58 cases.
abstract: OBJECTIVE
  Jugulotympanic paragangliomas (JTPs) are rare benign tumors whose surgical treatment is usually associated with partial resection of the lesion, high morbidity, and even death. Gamma Knife radiosurgery (GKRS) has been reported as a useful treatment option. The goal of this retrospective study is to analyze the role of GKRS in tumor volume control and clinical outcomes of these patients.
  
  
  METHODS
  A total of 75 patients with JTPs were treated with GKRS at the authors' center from 1995 to 2012. The authors analyzed those treated during this period to allow for a minimal observation time of 2 years. The MR images and clinical reports of these patients were reviewed to assess clinical and volumetric outcomes of the tumors. The radiological and clinical assessments, along with a group of prognostic factors measured, were analyzed using descriptive methods. The time to volumetric and clinical progression was analyzed using the Kaplan-Meier method. Prognostic factors were identified using log-rank statistics and multivariate Cox regression models.
  
  
  RESULTS
  The mean follow-up was 86.4 months. The authors observed volumetric tumor control in 94.8% of cases. In 67.2% of cases, tumor volume decreased by a mean of 40.1% from the original size. Of patients with previous tinnitus, 54% reported complete recovery. Improvement of other symptoms was observed in 34.5% of cases. Overall, clinical control was achieved in 91.4% of cases. Previous embolization and familial history of paraganglioma were selected as significant prognostic factors for volumetric response to GKRS treatment in the univariate analysis. In multivariate analysis, no factors were significantly correlated with progression-free survival. No patient died of side effects related to GKRS treatment or tumor progression.
  
  
  CONCLUSIONS
  Gamma Knife radiosurgery is an effective, safe, and efficient therapeutic option for the treatment of these tumors as a first-line treatment or in conjunction with traditional surgery, endovascular treatment, or conventional fractionated radiotherapy.
authors.affiliation: Department of Neurosurgery, Hospital Universitario La Paz, Madrid; and.
authors.forename: Maria Luisa
authors.initials: ML
authors.lastname: Gandía-González
authors.forename: M Elena
authors.initials: ME
authors.lastname: Kusak
authors.forename: Nuria Martínez
authors.initials: NM
authors.lastname: Moreno
authors.forename: Jorge Gutiérrez
authors.initials: JG
authors.lastname: Sárraga
authors.forename: Germán
authors.initials: G
authors.lastname: Rey
authors.forename: Roberto Martínez
authors.initials: RM
authors.lastname: Álvarez
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D005925:Glomus Jugulare Tumor / Q000150:complications / Q000601:surgery*; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D010235:Paraganglioma / Q000150:complications / Q000601:surgery*; D011379:Prognosis; D011874:Radiometry; D016634:Radiosurgery / Q000379:methods*; D016896:Treatment Outcome; D055815:Young Adult
keywords: CN = cranial nerve; GKRS = Gamma Knife radiosurgery; Gamma Knife radiosurgery; HR = hazard ratio; JTP = jugulotympanic paraganglioma; SRS = stereotactic radiosurgery; clinical outcome; jugulotympanic paraganglioma; stereotactic radiosurgery; tumor control