Earlier reports had suggested a link between vasectomy and prostate cancer, but this new study was larger, analyzing data from 363,726 men enrolled in a large cancer-prevention study from 1982 to 2012, of whom 7,451 died of prostate cancer. The researchers also studied a subgroup of 66,542 men, 9,133 of whom were given prostate cancer diagnoses from 1992 to 2011 but did not die of the disease. The analysis is in the Journal of Clinical Oncology.
The researchers found no difference in rates of prostate cancer incidence or mortality between men who had had vasectomies and those who had not. Nor were there any differences in rates of aggressive cancers, tumor stage at diagnosis, or Gleason scores above 8, which indicate the most aggressive tumors.
The largest previous study of the link, which found an association between vasectomy and the most lethal forms of prostate cancer, involved 800 deaths. This new study included more than 7,400.
“If I were considering vasectomy, I wouldn’t be worried about prostate cancer,” said the lead author, Eric J. Jacobs, an epidemiologist with the American Cancer Society.
“To lower the risk of the worst kind of prostate cancer,” he continued, “there are two things: maintain a healthy weight, and if you smoke, quit. Smoking and obesity have consistently been linked with the risk of fatal prostate cancer.”