SAN FRANCISCO — African American men with a history of gonorrhea were more likely to develop prostate cancer than were those without gonorrhea in a case-control study of 836 African American men, reported Aruna V. Sarma, Ph.D.
The population-based study also found associations between greater sexual activity or higher numbers of sexual partners and an increased risk for prostate cancer, she said at the annual meeting of the American Urological Association.
Data came from a detailed in-home epidemiologic interview completed by 719 cancer-free African American men in 1996 and 117 African American men in the same county diagnosed with prostate cancer between 1996 and 2001. The questionnaire was part of the Flint (Mich.) Men's Health Study, said Dr. Sarma of the University of Michigan, Ann Arbor.
The results support previous conjectures that sexual behavior and a history of sexually transmitted diseases may be related to an increased risk for prostate cancer among African American men compared with whites. African American men also get more advanced prostate cancer and have worse stage-specific survival rates than do whites.
The current analysis included men aged 40-79 years and was adjusted for differences in age, income, and education between men with and without prostate cancer.
Men with a history of gonorrhea were 80% more likely to develop prostate cancer than were men without gonorrhea. Dr. Sarma speculated that urethral colonization by gonorrhea might trigger inflammatory mediators that could increase the risk for prostate cancer.
Men with other sexually transmitted diseases also showed increased risks for prostate cancer (a 50% increase in men with syphilis, a 20% increase in men with herpes) compared with men without those diseases, but these associations were not statistically significant.
The risk of being diagnosed with prostate cancer was tripled in men with a history of more than 20 sexual partners, compared with men reporting 5 or fewer sexual partners. A prostate cancer diagnosis also was three times more common in men who said they had sex two to three times per month or per week than in men who said they had no sexual activity in the past 12 months.