Unfertile Men at Higher Risk of Cancer

Men who cannot produce sperm have a higher risk of developing cancer, a new study from Stanford University School of Medicine says.

Researchers found that men diagnosed azoospermic, who are infertile due to the absence of sperm in their ejaculations, are at higher risk of developing cancer. Also, diagnosis of azoospermia before age 30 is associated with an eight-fold increase of cancer in them.

About 5 to 10 percent of men evaluated for infertility have azoospermia.

"An azoospermic man's risk for developing cancer is similar to that for a typical man 10 years older," said Michael Eisenberg, MD, assistant professor of urology at the medical school and s lead author of the study, according to a news release.

There are generally two main reasons for azoospermia; one is called the Obstructive azoospermia where there is some blockage preventing the sperms from reaching the ejaculations while the second one is non-obstructive azoospermia, where there is no such blockage.

Data of the 2,238 infertile men analyzed for  the study came from the Texas Cancer Registry and the Baylor College of Medicine in Houston. In this group, about 451 had azoospermia, and 1,787 did not have the condition.

In the study, a majority of men had non-obstructive azoospermia. The testes of these men didn't produce enough sperm due to genetic reasons.

Researchers found that azoospermic men were about three times more likely to develop cancer than men who didn't have the condition. Even men who were infertile but not azoospermic had a statically insignificant higher risk of cancer than other men.

According to Eisenberg, certain genetic changes that lead to azoospermia may also pose a higher risk of cancer in men.

The study is published in the journal Fertility and Sterility.