A newly released Harvard medical study finds that vasectomy raises the risk of lethal prostate cancer. The findings are the result of a 24-year longitudinal study of 50,000 men. The report, published in the July 7th issue of the Journal of Clinical Oncology, says the danger appears to be highest among men who have had a vasectomy before the age of 38!
Cancer experts call these findings “extremely important,” suggesting the implications in birth control are now quite significant and suddenly push the issue of birth control on women. As it is, women face many potential side effects in dealing with birth control.
Researchers point out that even though the most dangerous forms of prostate cancer are rare, over the 24-year study, 1.6% of the men developed a lethal form of the disease. They say a 20% increase would raise that figure to less than 2%.
As for why a vasectomy might raise the increased prostate cancer risks, Kathy Wilson, a co-author of the study, says the reasons remain unclear. One possibility, yet to be confirmed in additional research, is that the operation somehow changes the protein composition of seminal fluid made in the prostate.
Even among men who have had regular PSA screenings, those who had vasectomies were said to be 56% at higher risk to develop fatal prostate cancer. They say evidence shows the link is stronger in men who had vasectomy at younger age—earlier than 38 years old.
Malcolm Mason, a research scholar at Cancer Research UK says, “The extra risk of developing prostate cancer after having a vasectomy appears to be small, but of the few that do go on to develop the disease a higher number will develop an aggressive form.”
Among those who counsel caution is Dr. Louis Kavoussi, chairman of urology at North Shore-LIJ Health System in New Hyde, New York. He calls for more research in a “better controlled fashion” before physicians apply these findings to clinical practice. “It’s not like cigarette smoking causing a large number of people to develop lung cancer.
Support for the study comes from a grant to the Harvard School for Public Health by the U.S. National Cancer Institute among others.