title: Cofactors with human papillomavirus in a population-based study of vulvar cancer.
abstract: BACKGROUND
  Human papillomavirus (HPV) has been previously associated with vulvar cancer. In a population-based study, we examined whether exposure to HPV, cigarette smoking, or herpes simplex virus 2 (HSV2) increases the risk of this cancer.
  
  
  METHODS
  Incident cases of in situ (n = 400) and invasive (n = 110) squamous cell vulvar cancer diagnosed among women living in the Seattle area from 1980 through 1994 were identified. Serum samples were analyzed for antibodies against specific HPV types and HSV2. HPV DNA in tumor tissue was detected by means of the polymerase chain reaction. In most analyses, case subjects were compared with population-based control subjects (n = 1403). Relative risks of developing vulvar cancer were estimated by use of adjusted odds ratios (ORs) and 95% confidence intervals (CIs).
  
  
  RESULTS
  Increased risks of in situ or invasive vulvar cancer were associated with HPV16 seropositivity (ORs = 3.6 [95% CI = 2.6-4.8] and 2.8 [95% CI = 1.7-4.7], respectively), current cigarette smoking (ORs = 6.4 [95% CI = 4.4-9.3] and 3.0 [95% CI = 1.7-5.3], respectively), and HSV2 seropositivity (ORs = 1.9 [95% CI = 1.4-2.6] and 1.5 [95% CI = 0.9-2.6], respectively). When the analysis was restricted to HPV16 DNA-positive tumors (in situ or invasive), the OR associated with HPV16 seropositivity was 4.5 (95% CI = 3.0-6.8). The OR for vulvar cancer was 18.8 (95% CI = 11.9-29.8) among current smokers who were HPV16 seropositive in comparison with never smokers who were HPV16 seronegative.
  
  
  CONCLUSIONS
  Current smoking, infection with HPV16, and infection with HSV2 are risk factors for vulvar cancer. Risk appears particularly strong among women who are both current smokers and HPV16 seropositive.
authors.affiliation: Division of Public Health Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA 98104-2092, USA.
authors.forename: M M
authors.initials: MM
authors.lastname: Madeleine
authors.forename: J R
authors.initials: JR
authors.lastname: Daling
authors.forename: J J
authors.initials: JJ
authors.lastname: Carter
authors.forename: G C
authors.initials: GC
authors.lastname: Wipf
authors.forename: S M
authors.initials: SM
authors.lastname: Schwartz
authors.forename: B
authors.initials: B
authors.lastname: McKnight
authors.forename: R J
authors.initials: RJ
authors.lastname: Kurman
authors.forename: A M
authors.initials: AM
authors.lastname: Beckmann
authors.forename: M E
authors.initials: ME
authors.lastname: Hagensee
authors.forename: D A
authors.initials: DA
authors.lastname: Galloway
mesh_terms: D000328:Adult; D000368:Aged; D002213:Capsid / Q000032:analysis*; D002278:Carcinoma in Situ / Q000453:epidemiology / Q000473:pathology / Q000821:virology; D002294:Carcinoma, Squamous Cell / Q000097:blood / Q000453:epidemiology* / Q000473:pathology / Q000821:virology*; D016022:Case-Control Studies; D016001:Confidence Intervals; D004279:DNA, Viral / Q000032:analysis*; D005260:Female; D018258:Herpesvirus 2, Human / Q000302:isolation & purification; D006801:Humans; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D016017:Odds Ratio; D027383:Papillomaviridae / Q000302:isolation & purification*; D016133:Polymerase Chain Reaction / Q000379:methods; D012016:Reference Values; D012307:Risk Factors; D012959:Socioeconomic Factors; D014846:Vulvar Neoplasms / Q000097:blood / Q000453:epidemiology* / Q000473:pathology / Q000821:virology*; D014861:Washington
chemical_list: D004279:DNA, Viral