title: Conservative management of vestibular schwannoma: expectations based on the length of the observation period.
abstract: OBJECTIVE
  Evaluate long-term prevalence of tumor growth and need for further treatment in patients with a vestibular schwannoma treated with conservative management.
  
  
  METHODS
  Retrospective chart review.
  
  
  METHODS
  Private neurotologic tertiary referral center.
  
  
  METHODS
  Vestibular schwannoma patients undergoing conservative management and previously studied (N = 114). Mean time to last magnetic resonance imaging was 4.8 years and to last follow-up was 6.4 years (maximum, 18.5 yr).
  
  
  METHODS
  Serial gadolinium-enhanced magnetic resonance imaging with size measurement.
  
  
  METHODS
  Change in maximum tumor dimension of 2 mm or higher (growth), further treatment, audiologic measures-pure-tone average, word recognition, AAO-HNS (American Academy of Otolaryngology-Head and Neck Surgery) hearing class.
  
  
  RESULTS
  Thirty-eight percent of tumors demonstrated growth; an average of 6.5 mm (SD, 3.8) at a mean rate of 3.1 mm per year. Of patients with no growth at 1 year or less, 20% grew by last follow-up. Overall, 31% had further treatment after a mean of 3.8 years (SD, 3.5; maximum, 18.5 yr). Of those followed for 5 to 10 years, 18% eventually had further treatment. Only 56% of growing tumors had further treatment by last follow-up; 14.8% with nongrowing tumors also had further treatment. Pure-tone average declined more in tumors that grew (mean Δ = 28.8 dB) than those that did not (mean Δ = 16.5 dB) (p ≤ 0.025), but there was no correlation between the amount of change in hearing and in the size of the tumor. Of patients with an initial AAO-HNS hearing Class A, 85.7% retained serviceable hearing.
  
  
  CONCLUSIONS
  For patients electing an observation approach to treatment of vestibular schwannoma, about 31% may eventually undergo further treatment. Of those followed for 5 to 10 years, 18% eventually had further treatment. However, some patients are followed with radiologic evaluations for many years without necessity for further treatment.
authors.affiliation: *House Research Institute and House Clinic, Los Angeles, California; †Ear, Nose and Throat Institute, Case Western Reserve School of Medicine, University Hospitals Case Medical Center, Cleveland, Ohio; ‡Department of Otolaryngology and Head & Neck Surgery, University of Kansas Medical Center, Kansas City, Kansas; and §Clinical Research Consultant to House Research Institute, Marina del Rey, California, U.S.A.
authors.forename: Jose N
authors.initials: JN
authors.lastname: Fayad
authors.forename: Maroun T
authors.initials: MT
authors.lastname: Semaan
authors.forename: James
authors.initials: J
authors.lastname: Lin
authors.forename: Karen I
authors.initials: KI
authors.lastname: Berliner
authors.forename: Derald E
authors.initials: DE
authors.lastname: Brackmann
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D006309:Hearing; D006320:Hearing Tests; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009464:Neuroma, Acoustic / Q000473:pathology*; D012189:Retrospective Studies; D016896:Treatment Outcome; D057832:Watchful Waiting