The new test focuses on a protein named prostate cancer antigen-2 (EPCA-2). This blood protein is produced in large amounts only by prostate cancer cells unlike the PSA test. The latter is found even in normal prostate cells and sometimes this might give false positive prostate cancer results.

Prostate cancer is the most common cancer in men in the United States. It is also the second leading cause of cancer deaths in the country. According to the American Cancer Society, 218,890 new cases of prostate cancer will be diagnosed in the United States this years and lead to at least 27,050 deaths.

The cancer is fully curable if detected early. However tests for diagnosing it are few and far between and the PSA test although reliable is not always accurate. In fact prostate cancer is known to be accidentally detected on autopsy in some cases. It is estimated that 1.3 million men will undergo biopsies to detect cancer in the US this year, but only 200,000 will have positive results.

Therefore prostate cancer needs to be diagnosed early and accurately to hike chances of survival. The new test promises accurate as well as improved diagnosis, according to lead researcher Dr. Robert H. Getzenberg, professor of urology and director of research at the James Buchanan Brady Urological Institute.

In the new study appearing in the latest issue of the journal Urology, the researchers measured the blood levels of EPCA-2 in 330 men. Among them some men had prostate cancer, but their PSA test was normal, while others had an enlarged prostate gland, which was not cancerous.

Researchers report 90 percent accuracy in diagnosing prostate cancer confined within the gland at a specific level of ECPA-2. The test was also able to diagnose prostate cancer in 98 percent of men in whom the cancer had spread outside the gland. Furthermore 97 percent of men tested negative for prostate cancer by the EPCA-2 test.

Current PSA testing methods do not have a high degree of accuracy and can only provide a rough guide to the presence or absence of cancer. High PSA levels may indicate cancer, but more often than not biopsies return negative results.

Getzenberg revealed the test was 97 percent specific based on their results. "We've been able to show that blood levels of it are low in normal individuals and high in prostate cancer, and that it distinguishes between cancers that are confined to the prostate and those that have spread outside the gland," he added.

"Clearly, we need further validation," Getzenberg admitted. "We are doing good-sized validation studies, and we are also testing the ability of the marker to identify aggressive forms of the disease."

His team has worked closely with researchers at the University of Pittsburgh and they have decided to license the ECPA-2 screen to a company called Onconome Inc. The researchers have already sounded out the Food and Drug Administration for approval of the test and hope to have it on the market in the next 18 months.

Dr. Durado Brooks, director of prostate and colorectal cancers at the American Cancer Society said the test looked promising, but more research was needed to validate it.

If the EPCA-2 test pans out, then it would save unnecessary biopsies in many cases and also help identify those prostate cancer patients in whom "wait and watch" rather than surgery is advised.