There have been several studies investigating the potential association between vasectomy and prostate cancer. Some studies have suggested a slight increase in the risk of developing prostate cancer among men who have had a vasectomy, while others have found no association.
A large study published in the Journal of the American Medical Association in 2017 analyzed data from over 300,000 men and found a small but statistically significant increase in the risk of prostate cancer among men who had a vasectomy. The study suggested that the increased risk may be related to inflammation caused by the vasectomy procedure.
However, other studies have found no association between vasectomy and prostate cancer, and some have even suggested a protective effect against the disease. A meta-analysis published in the Journal of Clinical Oncology in 2016 found no evidence of a significant association between vasectomy and prostate cancer.
The 2012 American Urological Association Guideline on Vasectomy states the following:
A meta-analysis of 10 comparative cohort studies was performed as part of the literature review.This analysis indicated that the relative risk of prostate cancer in vasectomized versus non-vasectomized men was not statistically significantly different (Relative risk (RR) 1.08; 95% confidence interval (CI) 0.88 to 1.32). Among studies that reported outcomes by years since vasectomy, meta-analysis revealed no relationship between time since vasectomy and prostate cancer (RR 1.00; 95% CI 0.58-1.73).There also was no relationship between age at time of vasectomy and prostate cancer. An additional group of case-control studies also was identified. The findings from these studies were too heterogeneous to allow pooling, but the majority of studies did not detect a relationship between prior vasectomy and prostate cancer and concluded that the statistical differences could be explained by high risk of selection bias.
It is therefore debatable whether there is a relationship between prostate cancer and vasectomy. If there is, the increased risk is very small. The official position of the American Urological Association is that the association between vasectomy and prostate cancer risk is so weak that it need not even be discussed as part of routine pro-op counseling. There are greater increases in the risk of prostate cancer (and mortality) associated with consuming milk / dairy products, meat (Association Between Red and Processed Meat Consumption and Risk of Prostate Cancer: A Systematic Review and Meta-Analysis) and alcohol (Is alcohol consumption a risk factor for prostate cancer? A systematic review and meta-analysis) or even having multiple sexual partners and not ejaculating often enough (Sexual Activity and Risk of Prostate Cancer: A Dose-Response Meta-Analysis).
