Soon, test to measure genetic risk of prostate cancer

A simple blood or urine test could soon identify men with an elevated, genetically-inherited risk for prostate cancer, suggests new research that spotted genetic risk factors associated with the disease.

"We developed a risk model that may have clinical value," said lead researcher John Witte, professor of epidemiology and biostatistics and of urology at the University of California-San Francisco.

"We also showed that there remain substantial undiscovered genetic risk factors for prostate cancer," Witte noted.

The study, which compared 7,783 men with prostate cancer to 38,595 men without the disease, is available online and will be published in an upcoming issue of the journal Cancer Discovery.

The researchers modelled prostate cancer risk using 105 specific bits of DNA that are associated with prostate cancer risk.

While they estimated that each of these genetic variants only modestly alters risk, they determined that men with combinations of these DNA variants placed them among the highest 10 percent for risk for prostate cancer.

The researchers determined that these men were more than six times as likely to be diagnosed with prostate cancer compared to the men who ranked among the lowest 10 percent for prostate cancer risk.

Men ranked in the highest percentiles for risk in the study have a prostate cancer risk comparable to the breast cancer risk among women who carry a mutation in one of the so-called breast cancer genes, BRCA1 or BRCA2, Witte said.

While women suspected of having mutated BRCA genes can choose to undergo commercially-available genetic testing, there is no routinely available clinical test to measure genetic risk for prostate cancer.