Men who have vasectomies do not have a higher risk of prostate cancer and are not more likely to die from the disease, according to a large, prospective study published in the Journal of Clinical Oncology.
“While a previous study suggested an association, our results show no connection between vasectomies and overall risk of prostate cancer, or of dying from prostate cancer, and should provide some reassurance to men considering vasectomy,” said lead study author Eric J. Jacobs, PhD, of the American Cancer Society in Atlanta, in a statement. “Men concerned about developing a fatal prostate cancer should focus on maintaining a healthy weight and, if they smoke, quitting smoking. Both obesity and smoking have consistently been linked with higher risk of fatal prostate cancer as well as with risk of many other diseases.”
In an analysis of 363,726 men who took part in the Cancer Prevention Study II (CPS-II), 7,451 men died of prostate cancer between 1982 and 2012. CPS-II recruited men 40 years of age and older and included 42,015 men who had undergone a vasectomy. The researchers found no association between vasectomy and prostate cancer mortality (hazard ratio [HR], 1.01 [95% CI, 0.93–1.10]).
In the CPS-II Nutrition Cohort, a subset of CPS-II that examined 66,542 men (9,133 of which were diagnosed with prostate cancer), vasectomy was also not associated with overall incidence of prostate cancer (HR, 1.02 [95% CI, 0.96–1.08]) or incidence of high-grade prostate cancer, defined as tumors with a Gleason score of 8 or greater (HR, 0.91 [95% CI, 0.78–1.07]).
Prior epidemiologic studies on the potential prostate cancer risk of vasectomy had mixed results, with some positive associations found in case-control studies. Among six relatively small prospective studies, three found a statistically significant link between the procedure and increased prostate cancer risk and three found no such association.
The current study found no association between vasectomy and risk of prostate cancer when the analysis was restricted to men aged 50 or older or when analyzed by the year the vasectomy was done.
“Men who have had a vasectomy or are considering one can now be assured that the procedure does not increase their risk of dying from prostate cancer,” said Sumanta Pal, MD, an ASCO expert in prostate cancer and a medical oncologist at the City of Hope Cancer Center in California, in a statement.
The analysis did show an increase in risk of nonaggressive prostate cancer during the last 5 years of the study period, but, according to the study authors, it is not clear if this result is simply due to chance.