Sexual partners, sexually transmitted infections, and prostate cancer risk

• Published in: Cancer epidemiology Vol. 38; no. 6; pp. 700 - 707
• Main Authors: Spence, Andrea R., Rousseau, Marie-Claude, Parent, Marie-Élise
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier Ltd 01.12.2014; Elsevier Limited; American Association for Cancer Research
• Subjects: Acquired immune deficiency syndrome; Adult; Aged; AIDS; Cancer; Epidemiology; Female; Hematology, Oncology and Palliative Medicine; HIV; Human health and pathology; Human immunodeficiency virus; Humans; Infectious diseases; Internal Medicine; Life Sciences; Male; Men; Middle Aged; Prostate cancer; Prostatic Neoplasms - epidemiology; Prostatic Neoplasms - etiology; Risk Factors; Sexual activity; Sexual orientation; Sexual Partners; Sexually Transmitted Diseases - complications; Sexually transmitted infections; Canada; Montreal Quebec Canada; Canada, Quebec, Montreal; OR; HIV; STI; AIDS; Sexual activity; Sexual orientation; CIs; Prostate cancer; Sexual partners; PCa; PSA; Sexually transmitted infections; sexually transmitted infection; odds ratio; prostate cancer; human immunodeficiency virus; confidence intervals; acquired immune deficiency syndrome; prostate-specific antigen
• ISSN: 1877-7821; 1877-783X; 1055-9965; 1877-783X; 1538-7755
• DOI: 10.1016/j.canep.2014.09.005

•Association between sexual activity and prostate cancer risk was examined.•Having had >20 female sexual partners associated with decreased prostate cancer risk.•Having had >20 male sexual partners were suggestive of greater prostate cancer risk.•Self-identification as a homosexual was suggestive of greater prostate cancer risk.•No association found between sexually transmitted infections and prostate cancer. Background: The etiology of prostate cancer (PCa) is poorly understood. Sexual activity and sexually transmitted infections (STIs) are among factors under scrutiny, with controversial findings to date. Methods: We examined the association between the number and gender of sexual partners, STIs and PCa risk in the context of PROtEuS, a population-based case–control study set amongst the mainly French-speaking population in Montreal, Canada. The study included 1590 histologically-confirmed PCa cases diagnosed in a Montreal French hospital between 2005 and 2009, and 1618 population controls ascertained from the French electoral list, Montreal residents, frequency-matched to cases by age. In-person interviews elicited information on sociodemographic, lifestyle and environmental factors. Unconditional logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) between sexually related factors and PCa risk, adjusting for age, ancestry, family history of PCa, and PCa screening history. Results: Subjects with more than 20 sexual partners in their lifetime had a decreased risk of PCa (OR 0.78, 95% CI 0.61–1.00) as did subjects who specifically had more than 20 female sexual partners (OR 0.72, 95% CI 0.56–0.94). By contrast, having had several male sexual partners appeared to confer some excess in risk of PCa. No association emerged for history of STIs and PCa but STIs prevalence was low. Conclusion: Our findings are in support of a role for the number of sexual partners in PCa development. The gender of sexual partners should be taken into account in future studies investigating this association.