New prostate cancer test evolved.
New Prostate Cancer Test More Specific, Sensitive Than PSA Test
ScienceDaily (May 16, 2011) — A new test for prostate cancer that measures levels of prostate specific antigen (PSA) as well as six specific antibodies found in the blood of men with the disease was more sensitive and more specific than the conventional PSA test used today, according to a study by researchers at UCLA’s Jonsson Comprehensive Cancer Center.
The test, called the A+PSA assay, also reduced the rate of false-positives, tests that indicate the presence of cancer when no disease is actually present, said Gang Zeng, an associate professor of urology, a Jonsson Cancer Center researcher and senior author of the study.
The retrospective study used blood taken before surgery from 131 patients from UCLA, Japan and France with biopsy-confirmed prostate cancers and compared results to blood taken from 121 men with either BPH or prostatitis, an infection or inflammation of the prostate that increases PSA levels. The study focused on six specific prostate-cancer associated antigens — NY-ESO-1, SSX-2,4, XAGE-lb, AMACR, p90 and LEDGF — which are found predominantly in patients with prostate cancer and not in benign prostate conditions.
The A+PSA assay looked simultaneously for PSA and antibodies to the six prostate-cancer associated antigens in a single reaction test done in a laboratory, much like PSA is measured. The new test takes about two hours, again similar to the PSA test. The test results in an index of numbers used to diagnose cancer, with a score of 0 to 0.5 indicating a benign result and 0.5 to 1 indicating the presence of prostate cancer, Zeng said.