Increased risk of aggressive prostate cancer following vasectomy

1. Vasectomy was associated with a small increased risk of aggressive prostate cancer on extended long-term follow-up.

Evidence Rating Level: 2 (Good)

Study Rundown: The association between prostate cancer and vasectomy has been controversial, with multiple large studies reporting both positive and no association. Criticism of studies showing an increased risk has focused on bias and possible confounding. The purpose of this study was to investigate this relationship more thoroughly by extended follow-up of the Health Professionals Follow-Up Study (HPFUS); furthermore, to evaluate the risk of advanced and lethal cancers.

At the conclusion of this study, the authors found a small positive association between vasectomy and prostate cancer. Furthermore, among the population of men undergoing intensive screening for prostate cancer, vasectomy was associated with an increased risk of advanced or lethal cancer. These results are supported by the large size of the cohort and extended follow-up. However, it should be noted that this was an observational study and that vasectomies were elective, thus introducing potential confounding.

Click to read the study in JCO

In-Depth [retrospective cohort]: This retrospective analysis drew data from a total of 12 321 men who had undergone vasectomies from the Health Professionals Follow-Up Study. After 24 years of follow-up, a total of 6023 cases of prostate cancer were diagnosed. The relative risk of total prostate cancer in men who had undergone a vasectomy compared to those who had not was 1.10 (95% CI, 1.04 to 1.17). Vasectomy was not associated with increased risk for low-grade cancer, but with lethal (RR 1.19; 95% CI, 1.00-1.43) and advanced stage disease (RR 1.20; 95% CI, 1.03 to 1.4) and high-grade cancer (RR 1.22; 95% CI, 1.03 to 1.45). In a highly screened cohort of 13901 men, vasectomy was associated with an increased risk of high-grade (RR 1.28; 95% CI, 0.91 to 1.81) and grade 7 cancers (RR 1.22; 95% CI, 1.02 to 1.47) as well as lethal cancers (RR 1.56; 95% CI, 1.03 to 2.36).

More from this author: Rituximab linked with reduced chronic immune disease following stem cell transplantation, High-dose prophylaxis for hemophilia increases costs with minimal benefit, Ambrisentan found ineffective against idiopathic pulmonary fibrosis

Image: PD

©2012-2014 2minutemedicine.com. All rights reserved. No works may be reproduced without expressed written consent from 2minutemedicine.com. Disclaimer: We present factual information directly from peer reviewed medical journals. No post should be construed as medical advice and is not intended as such by the authors, editors, staff or by 2minutemedicine.com. PLEASE SEE A HEALTHCARE PROVIDER IN YOUR AREA IF YOU SEEK MEDICAL ADVICE OF ANY SORT.