Circumcision May Prevent Certain Types of Cancer

New research shows that women who have circumcised sex partners could be less likely to get cervical cancer. The research appears in the current New England Journal of Medicine. It found that men with intact foreskins were three times likelier than circumcised men to be infected with the human papillomavirus (HPV), the virus that causes genital warts and most cases of cervical cancer.

The study was conducted in five different countries. Researchers discovered that HPV was present in about 20 percent of uncircumcised men, but less than 6 percent of circumcised men. Women had a 58 percent lower chance of developing cervical cancer if their current partner was uncircumcised, even if the partner had a history of multiple partners.

The researchers theorize that the skin in the inner lining of the foreskin is particularly vulnerable to the virus, which is believed to be responsible for 99 percent of all cases of cervical cancer, the second leading cancer among women all over the world.

"It will certainly fuel the ongoing debate about the merits of circumcision," said Dr. Michael Thun, an American Cancer Society epidemiologist commenting on the study. He said the findings raise the question of whether circumcision can reduce the spread of AIDS, too. Studies dating back to at least 1988 indicate that circumcision offers some protection against AIDS, but the research has not been conclusive and more definitive studies are ongoing.

The cervical cancer study examined about 3,800 women, half of whom had cervical cancer, and half of whom were cancer-free. There was only a slight overall difference between the two groups in how many had circumcised partners and how many had uncircumcised ones. However, the researchers found a strong difference in the risk of cervical cancer for women whose partners were especially active sexually. Women whose high-risk partners were not circumcised were five times more likely to get cancer than those whose partners were circumcised.

The researchers defined high-risk men as those who had at least six sex partners and started having sex before 17. Dr. Xavier Castellsague of the Catalan Institute for Oncology in Barcelona, Spain, said it would not be logical to promote circumcision to try and control cervical cancer in the United States, where Pap smears usually detect it at a treatable stage.

But he said circumcision could make a big difference in developing countries where there is no regular screening for cervical cancer. "If it is shown in trials to be effective, it could be a relatively simple and safe procedure to prevent these life-threatening infections," he said.

In an editorial that accompanied the study, Drs. Hans-Olov Adami of the Karolinska Institute in Stockholm and Dimitrios Trichopoulos of the Harvard School of Public Health said that "if we assume that 25 percent of the men around the world are circumcised, then the general adoption of circumcision might lead to a further reduction in the incidence of cancer of the cervix of 23 percent to 43 percent," and even reduce the risk of penile cancer, HIV and other infections. But they said other ways exist to reduce those risks, such as regular condom use and proper hygiene. An HPV vaccine is also now being tested. Whether promoting circumcision is "a realistic and quantitatively important addition to other strategies to combat cancer of the cervix," they said, "remains to be documented."