TUESDAY, March 26 (HealthDay News) -- Black men with early hair loss may have a heightened risk of developing prostate cancer, researchers report.

This study of more than 500 black men found that those "who have baldness by age 30 are more likely to develop prostate cancer," said researcher Charnita Zeigler-Johnson, a research assistant professor at the University of Pennsylvania's Center for Clinical Epidemiology and Biostatistics, in Philadelphia.

Researchers have looked at baldness as a potential risk factor for prostate cancer for years, but studies to date have produced conflicting findings. The new research is believed to be the first to focus only on blacks, Zeigler-Johnson said. Blacks in the United States get prostate cancer more often than other men and are more than twice as likely to die of the disease.

For the study, published in the April issue of Cancer Epidemiology, Biomarkers & Prevention, the researchers evaluated 318 men with prostate cancer and compared them to 219 men without the cancer. All were enrolled in the Study of Clinical Outcomes, Risk and Ethnicity between 1998 and 2010.

The men were asked about their hair loss, if any, at age 30. Options included: none, frontal (at the forehead or temples) and vertex (crown). They also supplied information on their medical history.

If the men reported baldness by 30, "their likelihood of developing prostate cancer was increased by about 70 percent, compared to men with no baldness at age 30," Zeigler-Johnson said.

While baldness of any type boosted risk, frontal baldness in younger men was most significant. "If they had frontal baldness at 30, men were 2.6 times more likely to be diagnosed with prostate cancer before age 60, compared to men at age 30 with no baldness," said Zeigler-Johnson.

For men diagnosed before age 60, frontal baldness was also strongly linked with more advanced and more aggressive cancers, she found.

Overall, 20 percent of those with cancer had baldness by age 30, but 13 percent of the group without cancer had baldness as well.

While the study found a link between early balding and prostate cancer, it didn't prove a cause-and-effect relationship. It does suggest a need for further study, however, experts noted.