Circumcision may slightly reduce a man's chances of developing prostate cancer, a new study suggests.
The findings are based on 3,399 men who answered a series of questions about their medical and sexual history. About half of them had been recently diagnosed with prostate cancer. The other half served as a control group.
The analysis revealed that men who had been circumcised before their first sexual intercourse were 15-per-cent less likely to develop prostate cancer than uncircumcised men.
What may account for these results? The researchers speculate that uncircumcised men are at increased risk of infections that may contribute to the development of prostate cancer.
"Men who haven't been circumcised still have their foreskin that provides folds of skin where infectious agents can grow and persist," said the senior researcher, Janet Stanford of the Fred Hutchinson Cancer Research Centre in Seattle. "Those infectious agents may travel to the prostate and start an inflammatory process … that is conducive to the growth of cancer cells."
Dr. Stanford hopes the study, published in the journal Cancer, will encourage other scientists to explore the possibility that circumcision may help prevent some cases of the disease.
Although a lot of work would be needed to prove a protective effect, the theory at least fits in with the latest trends in medical research. Recent studies, for instance, have suggested that circumcision can significantly reduce a man's risks of catching a sexually transmitted disease. (In fact, circumcision is now being promoted as an AIDS prevention strategy in Africa.)
Furthermore, a growing body of evidence indicates that several types of cancer are either triggered or fuelled by infections.
"This study is one piece of evidence supporting the theory that there may be an infectious-inflammatory process related to the development of some cases of prostate cancer," said Dr. Stanford.