title: Pelvic inflammatory disease and risk of invasive ovarian cancer and ovarian borderline tumors.
abstract: OBJECTIVE
  The aim of the study was to examine the potential association between a history of pelvic inflammatory disease (PID) and risk of epithelial ovarian cancer or ovarian borderline tumors.
  
  
  METHODS
  In a population-based case-control study in Denmark, we included 554 women with invasive ovarian cancer, 202 with ovarian borderline tumors, and 1,564 controls aged 35-79 years. The analyses were performed in multiple logistic regression models.
  
  
  RESULTS
  We found a significantly increased risk of ovarian borderline tumors among women with a history of PID (OR = 1.50; 95% CI 1.08-2.08) but no apparent association between PID and risk of invasive ovarian cancer (OR = 0.83; 95% CI 0.65-1.05). We found no effect of age at time of first PID or time since first PID on the risk for either condition.
  
  
  CONCLUSIONS
  Our results suggest that a history of PID is associated with an increased risk of ovarian borderline tumors, which may support the hypothesis that inflammation is an etiological factor. The lack of an association between previous PID and invasive ovarian cancer may indicate an etiological difference between ovarian borderline tumors and invasive ovarian cancer. However, an important limitation of the study is the use of self-reported PID.
authors.affiliation: Unit of Virus, Lifestyle and Genes, Danish Cancer Society Research Center, Copenhagen, Denmark.
authors.forename: Christina B
authors.initials: CB
authors.lastname: Rasmussen
authors.forename: Mette T
authors.initials: MT
authors.lastname: Faber
authors.forename: Allan
authors.initials: A
authors.lastname: Jensen
authors.forename: Estrid
authors.initials: E
authors.lastname: Høgdall
authors.forename: Claus
authors.initials: C
authors.lastname: Høgdall
authors.forename: Jan
authors.initials: J
authors.lastname: Blaakær
authors.forename: Susanne K
authors.initials: SK
authors.lastname: Kjaer
mesh_terms: D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D003718:Denmark / Q000453:epidemiology; D005260:Female; D006801:Humans; D016015:Logistic Models; D008875:Middle Aged; D010051:Ovarian Neoplasms / Q000453:epidemiology* / Q000209:etiology; D000292:Pelvic Inflammatory Disease / Q000150:complications / Q000453:epidemiology*; D012307:Risk Factors