title: Volume-outcome associations in head and neck cancer treatment: a systematic review and meta-analysis.
abstract: BACKGROUND
  Because of the relative rarity of head and neck malignancies and their complex treatment, some groups have advocated for regionalized care. Studies comparing high- and low-volume centers have demonstrated mixed results.
  
  
  METHODS
  We conducted a systematic review using MEDLINE and EMBASE including all studies examining a volume-outcome relationship in the treatment of patients with head and neck cancer with meta-analysis for long-term survival results.
  
  
  RESULTS
  Seventeen studies were identified. Meta-analysis was performed for studies that assessed long-term survival. High-volume hospitals (5 studies; hazard ratio [HR], 0.886; 95% confidence interval [CI], 0.820-0.956) and high-volume surgeons (2 studies; HR, 0.767; 95% CI, 0.641-0.919) have better overall survival than low-volume hospitals and surgeons, respectively.
  
  
  CONCLUSIONS
  Volume-outcome associations exist for head and neck oncologic procedures, although this has not been fully investigated for salivary gland malignancies. Future quality of care studies in head and neck oncology should focus on processes of care, which may explain this relationship.
authors.affiliation: Department of Otolaryngology - Head and Neck Surgery, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Antoine
authors.initials: A
authors.lastname: Eskander
authors.forename: Mazin
authors.initials: M
authors.lastname: Merdad
authors.forename: Jonathan C
authors.initials: JC
authors.lastname: Irish
authors.forename: Stephen F
authors.initials: SF
authors.lastname: Hall
authors.forename: Patti A
authors.initials: PA
authors.lastname: Groome
authors.forename: Jeremy L
authors.initials: JL
authors.lastname: Freeman
authors.forename: David R
authors.initials: DR
authors.lastname: Urbach
authors.forename: David P
authors.initials: DP
authors.lastname: Goldstein
mesh_terms: D006258:Head and Neck Neoplasms / Q000401:mortality / Q000601:surgery*; D061847:Hospitals, High-Volume; D061846:Hospitals, Low-Volume; D006801:Humans; D017063:Outcome Assessment, Health Care
keywords: free flap reconstruction; head and neck cancer; health services research; hospital volume; meta-analysis; neck dissection; surgeon volume; systematic review