On July 7, 2014, an article reporting a modest association between vasectomy and lethal prostate cancer was published online ahead of print in the Journal of Clinical Oncology (JCO).1 Lethal prostate cancer was defined as prostate cancer that caused death or metastases. The largest association reported was between vasectomy and lethal prostate cancer in a sub-group of men highly screened for prostate cancer. As a result of this report, a number of media outlets released articles linking vasectomy to an "increased risk of the most lethal kind of prostate cancer" and caused anxiety among many of the millions of men who already underwent vasectomies and those who are considering the procedure. On September 20, 2014 the article was formally released in the JCO print edition and is receiving continued media coverage.
Based on a careful review of vasectomy literature from 1949 to 2011 (including the 1992 and 1993 papers by Giovannucci and co-author Stampfer [who are co-authors of the 2014 JCO article] et. al.), the AUA Vasectomy Guideline Committee concluded in 2012 that there is no association between vasectomy and prostate cancer or other significant health risks. The 2012 AUA vasectomy guideline goes further by stating that there is no need for physicians to routinely discuss prostate cancer in their preoperative counseling of vasectomy patients.
Following the new JCO publication suggesting a relationship between vasectomy and aggressive prostate cancer, the AUA Vasectomy Guideline Panel carefully reviewed this new JCO report as well as additional literature published since the 2012 release of the Vasectomy Guideline. Additionally, a new meta-analysis was completed inclusive of both the previously reported literature from the 2012 guideline as well as the newly incorporated publication.
The review of the JCO article identified (a) methodological limitations regarding its ability to properly evaluate the risks of lethal prostate cancer; (b) inconsistencies with previous reports on the same cohort of men; and (c) a risk of bias due to potential residual confounding factors. These issues raise doubts about the validity of the results reported in the JCO article.
The new AUA meta-analysis produced results that are very similar to the results of the original meta-analysis reviewed in the 2012 guideline. The pooled relative risk ratio for the association between vasectomy and prostate cancer based on eight cohort studies is 1.05 (95% confidence interval 0.95 to 1.17), p = 0.33. The relationship is neither clinically nor statistically significant, indicating that when findings across the eight studies are combined, the overall conclusion is vasectomy is not associated with and is not a risk factor for prostate cancer.
Based on the newly examined literature and updated meta-analysis, the AUA Vasectomy Guideline Panel concludes that the preponderance of evidence is that there is no reason to change the statements in the 2012 AUA guideline on vasectomy. The Panel reaffirms vasectomy is not a risk factor for prostate cancer or for high grade prostate cancer and it is not necessary for physicians to routinely discuss prostate cancer in their preoperative counseling of vasectomy patients.
For more information, read the AUA Guideline on Vasectomy (Discussion of prostate cancer risk can be found on page 15).