title: Comorbidity and prognosis in head and neck cancers: Differences by subsite, stage, and human papillomavirus status.
abstract: BACKGROUND
  The prognostic utility of comorbidity on head and neck cancer may differ by subsite, stage, and human papillomavirus (HPV) status.
  
  
  METHODS
  We reviewed the medical records of 4953 patients with head and neck cancer for comorbidity (Charlson Comorbidity Index [CCI]), smoking, and alcohol history. Multivariate proportional hazards assessed the association of CCI with survival. HPV status was determined using p16 immunohistochemistry.
  
  
  RESULTS
  After accounting for stage, higher CCI was associated with worse overall survival (OS) in nasopharyngeal (hazard ratio [HR], 2.93; 95% confidence interval [CI], 1.53-5.62), oropharyngeal (HR, 1.99; 95% CI, 1.63-2.43), and oral cavity cancers (HR, 1.54; 95% CI, 1.27-1.86). These associations were most prominent in the early stage oral cavity (HR, 2.11; 95% CI, 1.50-2.96) and laryngeal (HR, 1.87; 95% CI, 1.35-2.58) cancers, and in advanced stage oropharyngeal (HR, 2.23; 95% CI, 1.81-2.74) and nasopharyngeal (HR, 3.50; 95% CI, 1.76-6.97) cancers. CCI was independently prognostic even in the HPV-adjusted oropharyngeal cancers.
  
  
  CONCLUSIONS
  Comorbidity was prognostic in subsets of nasopharyngeal, oropharyngeal, oral cavity, and laryngeal cancers. Comorbidity may be a partial surrogate for age and social habits.
authors.affiliation: Department of Medicine, Medical Biophysics, and Epidemiology, Ontario Cancer Institute, Princess Margaret Hospital/University Health Network, Toronto, Ontario, Canada; Department of Biostatistics, Princess Margaret Hospital, Toronto, Ontario, Canada.
authors.forename: Steven
authors.initials: S
authors.lastname: Habbous
authors.forename: Luke T G
authors.initials: LT
authors.lastname: Harland
authors.forename: Anthony
authors.initials: A
authors.lastname: La Delfa
authors.forename: Ehab
authors.initials: E
authors.lastname: Fadhel
authors.forename: Wei
authors.initials: W
authors.lastname: Xu
authors.forename: Fei-Fei
authors.initials: FF
authors.lastname: Liu
authors.forename: David
authors.initials: D
authors.lastname: Goldstein
authors.forename: John
authors.initials: J
authors.lastname: Waldron
authors.forename: Shao-Hui
authors.initials: SH
authors.lastname: Huang
authors.forename: Brian
authors.initials: B
authors.lastname: O'Sullivan
authors.forename: Geoffrey
authors.initials: G
authors.lastname: Liu
mesh_terms: D000368:Aged; D000428:Alcohol Drinking / Q000009:adverse effects; D002294:Carcinoma, Squamous Cell / Q000453:epidemiology* / Q000401:mortality / Q000628:therapy; D015897:Comorbidity; D005260:Female; D005500:Follow-Up Studies; D006258:Head and Neck Neoplasms / Q000453:epidemiology* / Q000401:mortality / Q000628:therapy; D006801:Humans; D015994:Incidence; D053208:Kaplan-Meier Estimate; D007822:Laryngeal Neoplasms / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D009062:Mouth Neoplasms / Q000453:epidemiology; D009303:Nasopharyngeal Neoplasms / Q000453:epidemiology; D009367:Neoplasm Staging; D009864:Ontario / Q000453:epidemiology; D009959:Oropharyngeal Neoplasms / Q000453:epidemiology; D027383:Papillomaviridae / Q000302:isolation & purification; D030361:Papillomavirus Infections / Q000453:epidemiology* / Q000821:virology; D011379:Prognosis; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects
keywords: Charlson Comorbidity Index; alcohol; head and neck cancer; human papillomavirus; mortality; smoking