Getting ‘the snip’ increases the risk of prostate cancer

Men who have a vasectomy have a 10% greater risk of getting prostate cancer, a major study has found.

The findings are based on an analysis of data on almost 50,000 men over a 24-year period.

One in four of the men — 12,321, had vasectomies.

There were 6,023 men diagnosed with prostate cancer, including 811 who died of the disease over the period from 1986 to 2010.

Researchers from the Harvard School of Public Health in the US found a 10% overall increased risk of prostate cancer in men who had a vasectomy.

A further analysis found a higher number of men who had vasectomies would go on to develop an aggressive form of the cancer.

Although the more aggressive form is rare, the risk was greater for men who had a vasectomy before the age of 38.

Researchers said their findings supported the suggestion that vasectomy was associated with a “modest” increased incident of lethal prostate cancer.

The study, published in the Journal of Clinical Oncology, points out that the cancer link was still evident in men who underwent regular blood (PSA) tests.

Concerns have been raised before about such studies — that the links could be the result of bias, but the researchers said they could rule those out.

One bias could be that men who have vasectomies are more likely to seek medical care or undergo more PSA tests.

Researchers also disregarded bias due to the possibility of sexually transmitted infections, sex hormone levels or cancer treatment.

In this study, 16 out of every 1,000 men developed lethal prostate cancer over the follow-up period, so vasectomy was linked to a 20% raised risk of lethal prostate cancer.

Although the 20% increase is significant, it is relatively small in the absolute risk of developing prostate cancer. In total, less that 2% developed the most aggressive form of the disease.

The Irish Cancer Society said the study had shown that the added risk of getting prostate cancer after a vasectomy was small.

“The researchers found that those men who went on to develop prostate cancer were more likely to develop an aggressive form, but this translates to a very small number of cases,” said the society’s acting head of research, Dr Sinéad Walsh.

Dr Walsh said it was important that men were aware of the risks of vasectomies.

Thousands of men in Ireland have had vasectomies, a procedure that seals the tubes that carry sperm from a man’s testicles to his penis and costs between €400 to €500.

In 2011, 3,451 men were diagnosed with prostate cancer and 518 died from the disease.

It is reckoned that one in eight men will develop the disease.

After non-melanoma skin cancer, prostate cancer is the second most common cancer in Ireland.

www.cancer.ie.