Male Infertility Linked To Prostate Cancer

By Margarita Nahapetyan

Male infertility is associated with an increased risk of developing the aggressive and potentially fatal form of prostate cancer, American researchers have found.

The experts say that men who have hard time conceiving a child are 2.6 times as likely to develop highly aggressive form of the disease when they age and 60 per cent more likely to have slow-growing tumors. "These results, if confirmed, also suggest that men identified with male factor infertility earlier in life may be considered for prostate cancer screening, given the elevated risk specifically for high-grade disease," said Dr. Thomas J. Walsh, MD, of the University of Washington School of Medicine in Seattle, who led the study.

Prostate cancer is one of the most common cancers among male population and the second highest killer, after lung cancer. Nearly 35,000 men every year are diagnosed with the condition, and 10,000 die. Sixty per cent of the victims have a non-aggressive form of the disease and in most cases can lead a healthy life. But the aggressive form can rapidly be fatal. However, while doctors can perform screenings for the prostate cancer, many men prefer not to do so because most tumors grow slowly and never cause any harm.

In the new study, the Washington team studied more than 22,500 men who had been evaluated for infertility at fifteen centers in California from 1967 to 1998. Researchers compared these men with a similar group of men without fertility problems from the general population. They reported later that 168 cases of prostate cancer among the men were identified, about the same as the 185 cases that would be expected in a group of that size. This suggests that just being evaluated for infertility does not affect the incidence of prostate cancer.

The findings revealed that over the following ten years after evaluation, 1.2 per cent of the men with infertility problems developed prostate cancer, compared to only 0.4 per cent of those who were fertile. After accounting for men's age, being infertile increased the chances of developing aggressive tumors 2.6 times. For slow-growing cancers, the risk went up 1.6 times.

According to Dr. Walsh, it is quite unlikely that being diagnosed with infertility directly results in the development of prostate cancer. Instead, both infertility and a higher risk of the disease might generate from a common genetic fault, or some aspect of men's lifestyle or environment. Age and diet also can contribute to the condition, with the prostate cancer being most common in older men and those who eat a diet high in fat and low in fruit and vegetables. Exercise may be protective, with a recent study finding that men who spend most of their working time sitting down are almost 30 per cent more likely to be diagnosed with prostate cancer, when compared to those with very active jobs.

The experts say that at this point it is not yet clear what could account for the relationship between male infertility and prostate cancer, but they speculate that damages to the male sex chromosome, such as an exposure to environmental toxins in the womb, may be involved. Other risk factors for prostate cancer include obesity, being African American and a family history of the disease.

The findings were published online on March 22 in the journal Cancer.