title: Increased risk of cancer in infertile men: analysis of U.S. claims data.
abstract: OBJECTIVE
  Aberrations in reproductive fitness may be a harbinger of medical diseases in men. Data suggest a higher risk of testicular cancer in infertile men. However, the relationship between infertility and other cancers remains uncertain.
  
  
  METHODS
  We analyzed subjects from the Truven Health MarketScan® claims database from 2001 to 2009. Infertile men were identified through diagnosis and treatment codes. Comparison groups were created of men who underwent vasectomy and a control cohort of men who were not infertile and had not undergone vasectomy. The incidence of cancer was compared to national U.S. estimates. Infertile men were also compared to men who underwent vasectomy and the control cohort using a Cox regression model.
  
  
  RESULTS
  A total of 76,083 infertile men were identified with an average age of 35.1 years. Overall 112,655 men who underwent vasectomy and 760,830 control men were assembled. Compared to age adjusted national averages, infertile, vasectomy and control subjects in the study cohorts had higher rates of all cancers and many individual cancers. In time to event analysis, infertile men had a higher risk of cancer than those who underwent vasectomy or controls. Infertile men had a higher risk of testis cancer, nonHodgkin lymphoma and all cancers than the vasectomy and control groups.
  
  
  CONCLUSIONS
  Consistent with prior reports, we identified an increased risk of testicular cancer in infertile men. The current data also suggest that infertile men are at an increased risk of all cancers in the years after infertility evaluation. Future research should focus on confirming these associations and elucidating pathways between infertility and cancer.
authors.affiliation: Department of Urology, Stanford University School of Medicine, Stanford, California; Department of Obstetrics/Gynecology, Stanford University School of Medicine, Stanford, California. Electronic address: eisenberg@stanford.edu.
authors.forename: Michael L
authors.initials: ML
authors.lastname: Eisenberg
authors.affiliation: Departments of Urology and Dermatology, Stanford University School of Medicine, Stanford, California.
authors.forename: Shufeng
authors.initials: S
authors.lastname: Li
authors.affiliation: Department of Urology, Stanford University School of Medicine, Stanford, California.
authors.forename: James D
authors.initials: JD
authors.lastname: Brooks
authors.affiliation: Department of Internal Medicine, Stanford University School of Medicine, Stanford, California.
authors.forename: Mark R
authors.initials: MR
authors.lastname: Cullen
authors.affiliation: Department of Health Research and Policy, Stanford University School of Medicine, Stanford, California.
authors.forename: Laurence C
authors.initials: LC
authors.lastname: Baker
mesh_terms: D000328:Adult; D016208:Databases, Factual; D006801:Humans; D007248:Infertility, Male / Q000150:complications*; D008297:Male; D009369:Neoplasms / Q000453:epidemiology* / Q000209:etiology*; D012306:Risk; D014481:United States
keywords: fertility; infertility; male; neoplasms