JUN 18, 2015

Paving the Way to Earlier Prostate Cancer Diagnosis

WRITTEN BY: Ilene Schneider

According to the National Cancer Institute, prostate cancer is the most common cancer in men in the United States, after skin cancer, and the second leading cause of death from cancer in men. Occurring more often in African-American men than in white men, prostate cancer claims the lives of more African-American men than white men. Nearly all prostate cancers are adenocarcinomas (cancers that begin in cells that make and release mucus and other fluids). Prostate cancer, which often has no early symptoms, usually grows very slowly. Most men who have prostate cancer are older than 65 years and usually die from something other than the disease (http://www.cancer.gov/types/prostate).

Now scientists at UC San Francisco and Kaiser Permanente Northern California believe that they can achieve earlier diagnosis of the disease by screening men with an elevated, genetically inherited risk for prostate cancer using a simple blood or urine test. The study, which compared 7,783 men with prostate cancer to 38,595 without the disease, was reported in Science Daily and will be published in Cancer Discovery (Pete Farley, University of California, San Francisco (UCSF). "Tests to gauge genetic risks for prostate cancer now are feasible." ScienceDaily. ScienceDaily, 17 June 2015) (www.sciencedaily.com/releases/2015/06/150617162032.htm).

According to the Science Daily article, "The new study is one of the first to come out of the collaboration between UCSF and Kaiser Permanente Research Program on Genes, Environment, and Health (RPGEH), which analyzed genetic samples and health records from more than 100,000 volunteers, making it one of the largest research projects in the United States to examine the genetic, health and environmental factors that influence common diseases such as prostate cancer."

Using 105 specific bits of DNA that commonly vary among individuals and are associated with prostate cancer risk, the researchers concluded that men with combinations of these DNA variants that placed them at high risk were more than six times as likely to be diagnosed with prostate cancer as compared with the men who ranked at low risk. Researchers said that men who were 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. Although women suspected of having mutated BRCA genes can undergo commercially available genetic testing, there is no comparable clinical test to measure genetic risk for prostate cancer.

As John Witte, PhD, a UCSF professor of epidemiology and biostatistics and of urology, who led the study along with Stephen Van Den Eeden, PhD, at Kaiser Permanente, "We developed a risk model that may have clinical value. We also showed that there remain substantial undiscovered genetic risk factors for prostate cancer."