Vasectomy is associated with an increased incidence of lethal prostate cancer.

This study was published in the Journal of Clinical Oncology 2014 Jul 7

Study title and authors:
Vasectomy and Risk of Aggressive Prostate Cancer: A 24-Year Follow-Up Study.

Siddiqui MM, Wilson KM, Epstein MM, Rider JR, Martin NE, Stampfer MJ, Giovannucci EL, Mucci LA.
Harvard School of Public Health

This study can be accessed at: http://www.ncbi.nlm.nih.gov/pubmed/25002716

This study investigated the association between vasectomy and prostate cancer risk. The study included 49,405 men, aged 40 to 75 years, who were followed for 24 years.

The study found:
(a) Men who had undergone vasectomy had a 10% increased risk of prostate cancer compared to men who had not had a vasectomy.
(b) Men who had undergone vasectomy had a 22% increased risk of high-grade prostate cancer compared to men who had not had a vasectomy.
(c) Men who had undergone vasectomy had a 19% increased risk of death or distant metastasis compared to men who had not had a vasectomy. (Distant metastasis refers to cancer that has spread from the original tumour to distant organs or distant lymph nodes).