An experimental blood test for prostate cancer seems to work better than the current PSA test and can tell whether the cancer is spreading.
The test is being developed by Robert H. Getzenberg, PhD, director of urology research at Johns Hopkins University’s Brady Urological Institute. Getzenberg began the work while still at the University of Pittsburgh; the test has been licensed to the Seattle biotech firm Onconome Inc.
The new test looks for a protein called EPCA-2 — or early prostate cancer antigen 2. Unlike the PSA (prostate-specific antigen) protein on which the current PSA test is based, this protein isn’t found in normal prostate cells. Instead, EPCA-2 occurs in relatively large amounts only in prostate cancer cells.
“We found it is very unique. It is 97% specific, meaning that if you test positive there’s only a 3% chance you don’t have prostate cancer,” the researchers said.
Getzenberg has a financial interest in the test. But experts who do not stand to gain from the test agree that it has enormous potential.
Otis Brawley, MD, chief of the solid tumor service at Emory University’s Winship Cancer Institute, calls the test “important” and predicts it will be widely used.
