Men with a history of the sexually transmitted disease gonorrhea may face a higher risk of prostate cancer, a study suggests.

The findings, from a study of more than 800 African-American men, add to evidence that STDs may contribute to the development of prostate cancer. Researchers suspect that chronic inflammation in the prostate gland, caused by infection, may over time promote tumor development.

Of the 40- to 79-year-old men in the current study, those with a history of gonorrhea were 78 percent more likely to develop prostate cancer than men who’d never had the STD.

In addition, men who reported the most sexual partners - 25 or more over their lives - had a nearly three times greater risk of the cancer than men who’d had five or fewer partners. This further suggests a role for “sexually transmitted factors” in prostate cancer risk, the researchers report in the Journal of Urology.

Past studies have found associations between STDs and prostate cancer risk in white men. The current study focused on black men, who have significantly higher rates of both prostate cancer and STDs such as gonorrhea.

Taken together, the evidence suggests that a history of STD infection may be a risk factor for prostate cancer, according to lead author Dr. Aruna V. Sarma, an assistant research scientist in urology at the University of Michigan in Ann Arbor.

But to confirm that, she told Reuters Health, researchers need to conduct studies where they not only look at relationships between STD history and prostate cancer risk, but also examine blood and tissue samples for markers of STD infection and chronic inflammation.

If STD infection is indeed a risk factor for prostate cancer, there will be important implications for prevention, according to Sarma.

There are few known modifiable risk factors for prostate cancer, she noted, so the link between the cancer and STDs like gonorrhea needs to be investigated further.

SOURCE: Journal of Urology, September 2006.