title: Outcomes and prognostic factors for squamous-cell carcinoma of the anal canal: analysis of patients from the National Cancer Data Base.
abstract: OBJECTIVE
  The objective of this study was to assess survival and prognostic factors for anal carcinoma in the population.
  
  
  METHODS
  Patients with squamous-cell carcinoma of the anal canal were identified from the National Cancer Data Base (1985-2000). Univariate and multivariable methods were used to assess factors associated with survival. Concordance was calculated to assess agreement between American Joint Committee on Cancer stage and actual outcome.
  
  
  RESULTS
  Nineteen thousand one hundred ninety-nine patients with anal carcinoma were identified (Stage I, 25.3 percent; Stage II, 51.8 percent; Stage III, 17.1 percent; Stage IV, 5.7 percent). Overall five-year survival was 58.0 percent. The American Joint Committee on Cancer (6th edition) staging system provided good survival discrimination by stage: I, 69.5 percent; II, 59.0 percent; III, 40.6 percent; and IV, 18.7 percent (concordance index, 0.663). On multivariable analysis, patients with anal carcinoma had a higher risk of death if they were male, >or=65 years old, black, living in lower median incomes areas, and had more advanced T stage tumors, nodal or distant metastases, or poorly differentiated cancers (P < 0.0001). There was not a significant difference in survival by hospital type or year of diagnosis.
  
  
  CONCLUSIONS
  Although tumor characteristics and staging affect prognosis, patient factors, such as gender, race, and socioeconomic status, are also important prognostic factors for squamous-cell carcinoma of the anal canal.
authors.affiliation: Department of Surgery, Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60611, USA. k-bilimori@northwestern.edu
authors.forename: Karl Y
authors.initials: KY
authors.lastname: Bilimoria
authors.forename: David J
authors.initials: DJ
authors.lastname: Bentrem
authors.forename: Colin E
authors.initials: CE
authors.lastname: Rock
authors.forename: Andrew K
authors.initials: AK
authors.lastname: Stewart
authors.forename: Clifford Y
authors.initials: CY
authors.lastname: Ko
authors.forename: Amy
authors.initials: A
authors.lastname: Halverson
mesh_terms: D000368:Aged; D001005:Anus Neoplasms / Q000401:mortality* / Q000473:pathology / Q000601:surgery / Q000628:therapy; D002294:Carcinoma, Squamous Cell / Q000401:mortality* / Q000473:pathology / Q000601:surgery / Q000628:therapy; D003131:Combined Modality Therapy; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009362:Neoplasm Metastasis; D009367:Neoplasm Staging; D011379:Prognosis; D016016:Proportional Hazards Models; D016019:Survival Analysis