Dr. Whang Comments: This is a surprising study. This study showed that there is a modest increase in prostate cancer in men who had vasectomy. I have been performing vasectomies for over 20 years and have not seen an increase in prostate cancer in these patients. I don’t feel that this is reason to withhold a very important simple contraceptive technique.
Vasectomy and Risk of Aggressive Prostate Cancer: A 24-Year Follow-Up Study
1. Mohummad Minhaj Siddiqui,
2. Kathryn M. Wilson,
3. Mara M. Epstein,
4. Jennifer R. Rider,
5. Neil E. Martin,
6. Meir J. Stampfer,
7. Edward L. Giovannucci and
8. Lorelei A. Mucci
+ Author Affiliations
1. Mohummad Minhaj Siddiqui, Kathryn M. Wilson, Mara M. Epstein, Jennifer R. Rider, Meir J. Stampfer, Edward L. Giovannucci, and Lorelei A. Mucci, Brigham and Women’s Hospital; Kathryn M. Wilson, Mara M. Epstein, Jennifer R. Rider, Meir J. Stampfer, Edward L. Giovannucci, and Lorelei A. Mucci, Harvard School of Public Health; Neil E. Martin, Dana Farber Cancer Institute, Boston; and Mara M. Epstein, University of Massachusetts Medical School, Worcester, MA.
1. Corresponding author: Lorelei A. Mucci, ScD, Department of Epidemiology, Harvard School of Public Health, 677 Huntington Avenue, Boston, MA 02115; e-mail: firstname.lastname@example.org.
1. Both M.M.S. and K.M.W. contributed equally to this work. Both E.L.G. and L.A.M. share senior authorship.
Purpose Conflicting reports remain regarding the association between vasectomy, a common form of male contraception in the United States, and prostate cancer risk. We examined prospectively this association with extended follow-up and an emphasis on advanced and lethal disease.
Patients and Methods Among 49,405 US men in the Health Professionals Follow-Up Study, age 40 to 75 years at baseline in 1986, 6,023 patients with prostate cancer were diagnosed during the follow-up to 2010, including 811 lethal cases. In total, 12,321 men (25%) had vasectomies. We used Cox proportional hazards models to estimate the relative risk (RR) and 95% CIs of total, advanced, high-grade, and lethal disease, with adjustment for a variety of possible confounders.
Results Vasectomy was associated with a small increased risk of prostate cancer overall (RR, 1.10; 95% CI, 1.04 to 1.17). Risk was elevated for high-grade (Gleason score 8 to 10; RR, 1.22; 95% CI, 1.03 to 1.45) and lethal disease (death or distant metastasis; RR, 1.19; 95% CI, 1.00 to 1.43). Among a subcohort of men receiving regular prostate-specific antigen screening, the association with lethal cancer was stronger (RR, 1.56; 95% CI, 1.03 to 2.36). Vasectomy was not associated with the risk of low-grade or localized disease. Additional analyses suggested that the associations were not driven by differences in sex hormone levels, sexually transmitted infections, or cancer treatment.
Conclusion Our data support the hypothesis that vasectomy is associated with a modest increased incidence of lethal prostate cancer. The results do not appear to be due to detection bias, and confounding by infections or cancer treatment is unlikely.