Circumcision Reduces the Risk of Prostate Cancer
Circumcision may help to lower the risk of men developing prostate cancer, a new study suggests.
Scientists at the Fred Hutchinson Cancer Research Centre, Seattle, found that men who had been circumcised before the first time they had sex were 15 per cent less likely to develop the disease compared with uncircumcised men.
It's already known that some infections can cause cancer, and research has suggested that sexually transmitted infections may play a role in the development of prostate cancer. As circumcision helps protect against certain sexually transmitted infections, the researchers wanted to find out if it could also help protect against the development of prostate cancer.
For the study, the researchers analysed the medical records of 3,399 men, around half with prostate cancer and half without the disease. About 65 per cent of the men with prostate cancer had been circumcised compared with 69 per cent of the men without the disease.
Men who had been circumcised before the first time they had sex were 15 per cent less likely to develop prostate cancer compared with uncircumcised men, the study found. They were also 18 per cent less likely to develop the more aggressive form of prostate cancer and 12 per cent less likely to develop the less aggressive form of the disease, the study found. Sexually transmitted infections may lead to prostate cancer by causing chronic inflammation that creates a hospitable environment for cancer cells, the researchers said.
But circumcision may also protect against sexually transmitted infections - and prostate cancer - by toughening the inner foreskin of the penis, making it less susceptible to cuts and abrasions and preventing bacteria and viruses from entering the bloodstream.
Circumcision also gets rid of the moist space under the foreskin that may help pathogens to survive.
However, the researchers pointed out that this was an observational study and does not prove cause and effect. Oncologist Dr Jonathan Wright, who led the study, said the findings should not be used by parents in deciding whether or not to have their son circumcised.
He said: "These data are in line with an infectious/inflammatory pathway which may be involved in the risk of prostate cancer in some men. "Although observational only, these data suggest a biologically plausible mechanism through which circumcision may decrease the risk of prostate cancer. Future research of this relationship is warranted."
Medical Articles and Abstracts
- Countries with high circumcision prevalence have lower prostate cancer mortality.
Mitchell S Wachtel, Shengping Yang, Brian J Morris
J Urol. 2015 Mar 23. pii: S0022-5347(14)04772-7. doi: 10.1016
The present study determined the relationship of male circumcision (MC) prevalence with prostatic carcinoma mortality rate in the 85 countries globally for which data on each were available. MC prevalence in different countries were obtained from a WHO report and allocated to WHO categories of 81%-100%, 20%-80%, and 0%-19%. Prostatic carcinoma mortality data were from Globoscan, gross national income per capita as well as male life expectancy were from a World Bank report, and percentages of Jews and Muslims by country were from the Pew Research Institute and the North American Jewish Data Bank. Negative binomial regression was used to estimate prostatic carcinoma mortality rate ratios. Compared to countries with 81%-100% MC prevalence, prostatic carcinoma mortality rate was higher in those with MC prevalence of 0%-19% (adjusted OR [adjOR] =1.82; 95% CI 1.14, 2.91) and 20%-80% (adjOR = 1.80; 95% CI, 1.16, 2.78). Higher Muslim percentage (adjOR = 0.92 [95% CI 0.87, 0.98] for each 10% increase) and longer life expectancy (adjOR = 0.82 [95% CI 0.72, 0.93] for each 5 additional years) were associated with lower prostatic carcinoma mortality. Higher gross national income per capita (adjOR = 1.10 [95% CI 1.01, 1.20] for double this parameter) correlated with higher mortality. Compared with American countries, prostatic carcinoma mortality rate was similar in Eastern Mediterranean countries (adjOR = 1.02; 95% CI 0.58, 1.76), but was lower in European (adjOR = 0.60; 95% CI 0.50, 0.74) and Western Pacific countries (adjOR = 0.54, 95% CI 0.37, 0.78). Thus, prostate cancer mortality is significantly lower in countries in which MC prevalence exceeds 80%.