Little evidence that vasectomy raises prostate cancer risk

July 18, 2017

(HealthDay)—For men who have had or might undergo a vasectomy, there is good news: A major study finds scant evidence that the procedure raises their risk of prostate cancer.

"At most, there is a trivial association between vasectomy and that is unlikely to be causal," concluded a team led by Dr. R. Jeffrey Karnes, of the Mayo Clinic in Rochester, Minn.

The analysis, based on data from 53 studies on the subject, was published online July 17 in the journal JAMA Internal Medicine.

As the researchers noted, couples who want to avoid unintended pregnancy often place the responsibility on the female partner. And sometimes, conception occurs despite the use of or devices.

In contrast, vasectomy has a very low risk of . And, "given the lower costs and lower risk of complications for vasectomy compared with [female] tubal ligation, it is clear that vasectomy is underused and should be offered more routinely to couples," the researchers suggested.

Vasectomy is typically a 30-minute outpatient procedure where a local anesthetic is applied to the scrotum and a doctor makes a small incision, pulling out the vas deferens (tubes that transport sperm). These tubes are then either cut or blocked before re-insertion, preventing fertilization.

But one potential reason holding some men back from "the snip" could be fears that it might somehow raise their odds for prostate cancer. According to Karnes and colleagues, those fears were stoked in the 1980s and 1990s by isolated reports of an "association between vasectomy and the risk of prostate cancer."

That initial controversy has died down, however, with better-conducted studies in recent years finding no such link. To try to settle the controversy, the Mayo team pored over data from 53 studies conducted across the world, involving a total of more than 14 million men.

The studies typically compared prostate cancer rates for men of similar ages who'd either had a vasectomy or not. Study follow-up varied from just under 2 years to more than 24 years.

The result? Overall, there was no link at all between vasectomy and the "high-grade" aggressive prostate tumors that are a bigger threat to health. There was a "weak association"—about a 5 percent hike in relative risk—between vasectomy and any form of prostate cancer, but even that statistic might be due to other factors, the study authors said.

As the integrity and methodology of studies got better, any link between vasectomy and prostate cancer shrank to near zero, the investigators noted.

And even if such a link did exist, the researchers calculated it would translate to only a 0.6 percent rise over a lifetime in the absolute risk of prostate cancer for any one man who underwent a vasectomy.

"It is questionable whether such a small increased risk is important to the public," the study authors said.

Dr. David Samadi is chair of urology at Lenox Hill Hospital in New York City. He read the study and offered up an explanation for even the 0.6 percent rise in risk.

The finding "demonstrates the effects of 'health-seeking' activities among men undergoing vasectomy," he said. "Simply put, men who decide to go with vasectomy [tend to] visit physicians more often and get tested for [prostate-specific antigen] and prostate cancer more often than other men. This conscious health-seeking behavior leads to more prostate cancer diagnoses."

The bottom line, according to the Mayo team, is that "although patients should be appropriately counseled, concerns about the risk of prostate cancer should not preclude clinicians from offering vasectomy to couples seeking long-term contraception."

Samadi agreed. The new study "demonstrates that is a safe procedure, which does not increase the chance of in men," he said.

Explore further: Vasectomy may increase risk of aggressive prostate cancer

More information: David Samadi, M.D., chairman, urology & chief, robotic surgery, Lenox Hill Hospital, New York City; July 17, 2017, JAMA Internal Medicine, online

For more on vasectomies, head to the American Academy of Family Physicians.

Related Stories

Vasectomy may increase risk of aggressive prostate cancer

July 9, 2014
Vasectomy was associated with a small increased risk of prostate cancer, and a stronger risk for advanced or lethal prostate cancer according to a new study from Harvard School of Public Health (HSPH). The researchers found ...

Vasectomy may not raise prostate cancer risk after all

September 20, 2016
(HealthDay)—A large, new study challenges previous research that suggested vasectomies might increase the risk of prostate cancer or dying from it.

Vasectomy reversal outcomes up with same partner as before

January 9, 2015
(HealthDay)—Fertility outcomes are improved for men who undergo vasectomy reversal and have the same female partner as before vasectomy, according to a study published in the January issue of The Journal of Urology.

Risk factors for prostate cancer

September 30, 2015
New research suggests that age, race and family history are the biggest risk factors for a man to develop prostate cancer, although high blood pressure, high cholesterol, vitamin D deficiency, inflammation of prostate, and ...

Risk of all cancers, specific cancers up in infertile men

May 5, 2015
(HealthDay)—Infertile men have increased risk of all cancers and some individual cancers, according to a study published in the May issue of The Journal of Urology.

Body size and prostate cancer risk

July 14, 2017
Prostate cancer is the most common cancer in men in Europe and the second most frequently diagnosed cancer in men worldwide.

Recommended for you

Study prompts new ideas on cancers' origins

December 16, 2017
Rapidly dividing, yet aberrant stem cells are a major source of cancer. But a new study suggests that mature cells also play a key role in initiating cancer—a finding that could upend the way scientists think about the ...

What does hair loss have to teach us about cancer metastasis?

December 15, 2017
Understanding how cancer cells are able to metastasize—migrate from the primary tumor to distant sites in the body—and developing therapies to inhibit this process are the focus of many laboratories around the country. ...

Cancer immunotherapy may work better in patients with specific genes

December 15, 2017
Cancer cells arise when DNA is mutated, and these cells should be recognized as "foreign" by the immune system. However, cancer cells have found ways to evade detection by the immune system.

Scientists pinpoint gene to blame for poorer survival rate in early-onset breast cancer patients

December 15, 2017
A new study led by scientists at the University of Southampton has found that inherited variation in a particular gene may be to blame for the lower survival rate of patients diagnosed with early-onset breast cancer.

Scientists unlock structure of mTOR, a key cancer cell signaling protein

December 14, 2017
Researchers in the Sloan Kettering Institute have solved the structure of an important signaling molecule in cancer cells. They used a new technology called cryo-EM to visualize the structure in three dimensions. The detailed ...

'Bet hedging' explains the efficacy of many combination cancer therapies

December 14, 2017
The efficacy of many FDA-approved cancer drug combinations is not due to synergistic interactions between drugs, but rather to a form of "bet hedging," according to a new study published by Harvard Medical School researchers ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.