title: Management of patients with acoustic neuromas: a Markov decision analysis.
abstract: OBJECTIVE
  The management of patients with small (<1.5 cm) acoustic neuromas is controversial. Immediate treatment via microsurgical resection or radiosurgery is often advocated. A period of observation is sometimes advised followed by microsurgery or radiosurgery for tumors that demonstrate growth during the observation period. The purpose of this study is to calculate quality-adjusted life expectancy for the most commonly applied management strategies in hypothetical cohorts of patients of various ages.
  
  
  METHODS
  Markov decision analysis; societal perspective.
  
  
  METHODS
  Assumptions used in creating this model and event probabilities were obtained from a thorough literature review. Key parameters were identified and defined by the best available evidence. The main outcome measure is the benefit derived from each management strategy in quality-adjusted life years (QALYs). Sensitivity analysis was used to define benchmark performance information for these parameters.
  
  
  RESULTS
  The benefit of a period of observation followed by radiosurgery, if needed, for significant tumor growth is greater then all other strategies for all age groups and both sexes. When compared to observation followed by microsurgery, the additional benefit is small. QALY totals for the two immediate treatment groups were significantly lower than that for the observation groups.
  
  
  CONCLUSIONS
  For patients of all ages, a period of observation during which tumor growth and hearing thresholds are closely monitored is the superior strategy. For tumors that grow substantially or when hearing deteriorates, definitive management via radiosurgery is recommended.
authors.affiliation: Section of Otolaryngology, Dartmouth Medical School, Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire 03756, USA. daniel.morrison@hitchcock.org
authors.forename: Daniel
authors.initials: D
authors.lastname: Morrison
mesh_terms: D000328:Adult; D000368:Aged; D001309:Auditory Threshold; D003661:Decision Support Techniques; D005260:Female; D006801:Humans; D008297:Male; D008390:Markov Chains; D008866:Microsurgery / Q000379:methods* / Q000523:psychology; D008875:Middle Aged; D009464:Neuroma, Acoustic / Q000503:physiopathology / Q000523:psychology / Q000601:surgery*; D013506:Otologic Surgical Procedures / Q000379:methods* / Q000523:psychology; D011788:Quality of Life; D019057:Quality-Adjusted Life Years; D016634:Radiosurgery / Q000379:methods* / Q000523:psychology; D018570:Risk Assessment; D016896:Treatment Outcome