(RxWiki News) The standard test for prostate cancer has been around for 30 years. A new test is being developed that screens for more than PSA to pinpoint the cancer more reliably.
Scientists are refining a new prostate cancer test that measures not just prostate specific antigen (PSA) levels, but also six more specific antibodies (infection-fighting proteins) that are seen with the disease.
"New test may diagnose prostate cancer more accurately."
“This is a very promising new approach,” said Gang Zeng, an associate professor of urology, a Jonsson Cancer Center researcher and senior author of the study. “Instead of using just one parameter, PSA, to test for prostate cancer, we use multiple parameters that can be measured in a single reaction.”
The test, which is known as the A+PSA assay, also reduced the number of false-positives - results showing prostate cancer is present when it really isn't.
The study examined blood taken before surgery from 131 prostate cancer patients from UCLA, Japan and France. Those samples were compared to blood taken from 121 men who had other non-cancerous prostate disorders that also increase PSA levels.
The study focused on six specific prostate-cancer associated antigens – NY-ESO-1, SSX-2,4, XAGE-lb, AMACR, p90 and LEDGF. These proteins predominantly in prostate cancer, but not as often in benign prostate conditions such as BPH and prostatis.
A+PSA was more effective than the conventional PSA test in correctly diagnosing prostate cancer and reduced the number of false-positives.
“While measuring PSA is useful in identifying men with prostate cancer, some men with prostate cancer have a normal PSA level and small elevations in PSA above normal may be produced both by prostate cancer as well as an enlarged but benign prostate,” said Dr. Allan Pantuck, an associate professor of urology, Jonsson Cancer Center researcher and a study author. “Combining PSA with a panel of tests that measure an individual man’s anti-cancer immune response may better identify who has prostate cancer and who can be spared an unnecessary invasive biopsy.”
The new test is being refined to ensure the utmost accuracy. “Different men may have different levels of the six antibodies or different antibodies all together based on their race, age and ethnicity,” Zeng said. “We want as accurate an assay as we can possibly develop.”
This new prostate cancer test will have to be approved by the U.S. Food & Drug Administration.