Studies Suggest Link Between Prostate Cancer, Vasectomies

Two new studies suggest vasectomies increase men’s likelihood of developing prostate cancer, but outside experts question the findings and urge men with vasectomies not to get them reversed.

Men considering the procedure should weigh the benefits and risks of various birth-control methods before choosing one, along with their partners, doctors said.

The findings appear in today’s issue of the Journal of the American Medical Assn.

Both studies found about a 60% elevated risk of prostate cancer among men who had undergone vasectomies.

“We found 113 cases of prostate cancer among (a total of) 22,000 men who had had a vasectomy,” said the studies’ director, Dr. Edward Giovannucci, an epidemiologist at Harvard-affiliated Brigham and Women’s Hospital. “This compares to a rate of 70 cases per 22,000 among men who didn’t have a vasectomy.”

The elevated risk occurred 15 to 20 years after the procedure, said the researchers, who controlled statistically for differences in diet, smoking and other traits that could affect cancer rates.

The American Urological Assn. urged men with vasectomies to not reverse them in an attempt to prevent cancer, and Giovannucci agreed with that stance.

“It’s not at all clear this is really a relationship,” said Dr. Stuart S. Howards, a urology professor at the University of Virginia Medical School, who helped formulate the urological group’s position. “And if it is, we don’t know the reason--so we don’t know that reversing vasectomies would be effective.”

Men who have had vasectomies more than 20 years ago should be tested yearly for prostate cancer, the Urological Assn. said.