that a positive PCA3 was a more reliable indicator of cancer than a positive PSA. Seventy-eight percent of men with positive PCA3 results had cancer versus 21 percent of men with positive PSA scores.
The study confirmed the PCA3 has a high-false negative rate, which is why it is not seen as a replacement for the PSA. Just 49 percent of men with a negative PCA3 were cancer-free versus 87 percent of men with negative PSA scores.
As I previously reported, the PCA3 test detects genetic material from the PCA3 gene, which is 65 times more common in prostate cancer cells than normal cells.
Gen-Probe has completed enrollment in a 500-patient pivotal study that will determine whether the PCA3 test can reliably predict which men need a second biopsy following a first negative biopsy and positive PSA result. The company expects to have the results in time to submit a marketing application for the device to the FDA in the third quarter, Watts said. The test, which is available in Europe, could reach the U.S. market in 2011.