Scientists report new, more accurate prostate test

Scientists on Wednesday announced the development of an innovative experimental blood test for prostate cancer that could change the way men are screened for prostate cancer, the most common cancer in men and the second leading cause of cancer-related death in men.

The groundbreaking research study, conducted under the direction of Robert H. Getzenberg PhD, professor of urology and director of research at the James Buchanan Brady Urological Institute at the Johns Hopkins University School of Medicine, appeared Wednesday in the medical journal Urology.

The study narrates about a newly discovered blood protein, ProstaMark EPCA-2 (Early Prostate Cancer Antigen) that could offer an innovative method to treat the most common malignancy in men, Prostate cancer.

The difference, according to the study underwritten by a grant from Onconome, Inc., a privately held Seattle based biotechnology company, is that the experimental blood test, called EPCA-2 (Early Prostate Cancer Antigen), detects a chemical made principally in cancerous tissue, while the current prostate-specific antigen (PSA) test measures a protein normally produced by the prostate.

The new experimental prostate cancer test that relies on measuring levels of the newly discovered blood protein EPCA-2 significantly identified which male patients did have the cancer and which men did not have the cancer, a significant improvement over PSA, which has been the standard in the effort to detect prostate cancer for the last 25 years, though, it is not highly specific or sensitive.

The simple to use EPCA-2 test accurately detected 94 percent of men with prostate cancer and identified an unprecedented 97 percent of men who don't have the disease, the Hopkins study showed.

In contrast, figures from the National Cancer Institute and others have shown the PSA test has specificity rate as low as 15 to 30 percent. "The PSA test is not very specific to prostate cancer, and that's its biggest issue," lead study researcher Getzenberg said. "For men with elevated PSA levels, only one in six who get biopsies today actually have prostate cancer," he explained. "This amounts to 1.3 million to 1.6 million men being biopsied to find the 230,000 or so who actually have prostate cancer."

The EPCA-2 test not only identified prostate cancer, but it also could determine if the cancer had spread to other parts of the body, the study says.

EPCA-2 developers hope the new test, which is still under study and not yet commercially available, may help eliminate tens of thousands of unnecessary biopsies, and soon change the way doctors screen patients for the disease.

"The results from the Johns Hopkins University research study demonstrate that the ProstaMark EPCA-2 test is highly specific and sensitive to prostate cancer and could greatly reduce the number of unnecessary prostate biopsies," said Ray Cairncross, Onconome's CEO and Co-Founder.

Prostate cancer can be cured if detected early. Despite advances in early detection, nearly 40% of patients experience recurrence and this form of tumor remains the second most common cancer in men in the US. Nearly 230,000 American men are diagnosed with prostate cancer each year, and about 30,000 die of it. The death rate is 2.5 times higher among blacks than among whites.

Although, most of the researchers found the results of this most recent study exciting, but the new test is not perfect for some others, contending that Getzenberg and his colleagues tried it on 35 men with severe "benign prostatic hypertrophy", enlargement of the prostate that sometimes makes the PSA go up but is not cancer.

Meanwhile, the biotech company is seeking FDA approval to market the test, which it said will take at least a year or two before the test becomes commercially available.