title: Vestibular Schwannoma: The Evolution of Hearing and Tumor Size in Natural Course and after Treatment by LINAC Stereotactic Radiosurgery.
abstract: OBJECTIVE
  To review the natural course of tumor size and hearing during conservative management of 151 patients with unilateral vestibular schwannoma (VS), and to evaluate the same parameters for the part of the group (n = 84) who were treated by LINAC stereotactic radiosurgery (SRS).
  
  
  METHODS
  In prospectively collected data, patients underwent MRI and complete audiovestibular tests at inclusion, during the conservative management period and after SRS. Hearing was graded according to the Gardner-Robertson (GR) scale and tumor size according to Koos. Statistics were performed using Kaplan-Meier survival analysis and multivariate analyses including linear and logistic regression. Specific insight was given to patients with serviceable hearing.
  
  
  RESULTS
  During the conservative management period (mean follow-up time: 24 months, range: 6-96), the annual risk of GR class degradation was 6% for GRI and 15% for GR II patients. Hearing loss as an initial symptom was highly predictive of further hearing loss (p = 0.003). Tumor growth reached 25%. For SRS patients, functional hearing preservation was 51% at 1 year and 36% at 3 years. Tumor control was 94 and 91%, respectively.
  
  
  CONCLUSIONS
  In VS patients, hearing loss at the time of diagnosis is a predictor of poorer hearing outcome. LINAC SRS is efficient for tumor control. Patients who preserved their pretreatment hearing presented less hearing loss per year after SRS than before treatment, suggesting a protective effect of SRS when cochlear function can be preserved.
authors.affiliation: Departments of Otolaryngology, Head and Neck Surgery, Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland.
authors.forename: Christos
authors.initials: C
authors.lastname: Ikonomidis
authors.forename: Alessia
authors.initials: A
authors.lastname: Pica
authors.forename: Jocelyne
authors.initials: J
authors.lastname: Bloch
authors.forename: Raphael
authors.initials: R
authors.lastname: Maire
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018450:Disease Progression; D005260:Female; D034381:Hearing Loss / Q000209:etiology / Q000503:physiopathology*; D006320:Hearing Tests; D006801:Humans; D016014:Linear Models; D016015:Logistic Models; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009464:Neuroma, Acoustic / Q000150:complications / Q000473:pathology / Q000628:therapy*; D011446:Prospective Studies; D016634:Radiosurgery; D016896:Treatment Outcome; D047368:Tumor Burden; D057832:Watchful Waiting; D055815:Young Adult