Vasectomy and Risk of Prostate Cancer: How to Weigh Current Evidence

Vasectomy and prostate cancer risk: a meta-analysis of prospective studies

Epidemiological cohort studies investigating the association between vasectomy and prostate cancer risk have yielded inconsistent results. The aim of the present meta-analysis is to update the evidence on the association between vasectomy and prostate cancer. A comprehensively literature search of relevant studies was performed in December 2019 using PubMed. A DerSimonian and Laird random-effects model was used to calculate the summary relative risk (RR) and its 95% confidence interval (CI). A total of 15 eligible cohort studies (16 data sets) with more than four million of participants were eventually included in this meta-analysis. There was a statistically significant higher risk of prostate cancer among men who underwent vasectomy (RR: 1.09, 95% CI: 1.04-1.13) with obvious heterogeneity among included studies (P < 0.001, I2 = 64.2%). Vasectomy was also associated with the risk of advanced prostate cancer (RR: 1.07, 95% CI: 1.02-1.13), which is less likely to be affected from detection bias. In conclusion, findings from this meta-analysis of prospective studies indicate that vasectomy may be positively associated with the risk of prostate cancer. Further large prospective studies with long follow-up are warranted to verify the findings from this meta-analysis. In addition, the potential underlying molecular mechanism needed further exploration with in vitro and animal studies.

Long-term safety, health and mental status in men with vasectomy

Vasectomy is an efficient male contraceptive method, but the long-term effects of this technology in a large population are unclear. To investigate the influence of vasectomy on long-term health effects, we recruited 485 men with a vasectomy and 1940 men without vasectomy in China. After obtaining basic information from the Aging Males’ Symptoms (AMS) scale and other questionnaires, peripheral blood was drawn to assess the hormone levels, prostate specific antigen (PSA) and blood biochemistry. Using multiple linear regression analysis, these factors had no relationship with vasectomy except for four factors including the Somatic score (0.31, 0.02 and 0.61) in AMS, SF-36 score (−18.8, −32.00 and −5.60), “Role emotional” (−6.28, −10.34 and −2.22) and “Mental health” (−1.55, −3.08 and −0.02). A stratified analysis showed that with increased age, smoking and drinking, residence in township or a higher level of education, the mental health of men was worse. Vasectomy had no long-term effect on the level of sexual hormones in men, and it did not increase the level of PSA. The impact of the vasectomy on quality of life in men were mainly reflected in psychological effects, which suggests that men with vasectomy groups many benefit from professional psychological counseling.