New Test for Prostate Cancer Is Superior to PSA
A new test for prostate cancer, believed to be much more accurate than the PSA test, is expected to be approved soon. The test, currently undergoing large-scale clinical trials, measures the blood protein EPCA-2. Not only can it detect prostate cancer more effectively than measurement of prostate specific antigens (PSA), it also can determine the aggressiveness of the cancer and whether it has already spread.
In recent studies of 385 men, those with elevated EPCA-2 test results were found to have cancer 94% of the time, compared with 19% of those showing elevated PSA results. Only 3% showed false positive results and about 6% of existing cancers were missed using the new EPCA-2 blood protein markers. These results compare more favorably than the PSA test, which misses about 15% of existing cancers and gives a high level of false positives.
Every year, about 1.6 million men have unnecessary biopsies because of elevated PSA scores, whereas only about 230,000 of them actually are shown to have cancer. The digital rectal exam (DRE) is also not definitive in detecting this common cancer of men.
Prostate cancer is diagnosed in 230,000 new cases annually, and about 27,000 men die of the disease. The current PSA and DRE detection procedures are also deficient in that they cannot distinguish between cancer’s aggressive form, which is frequently fatal, and a slow-growing variety where “watchful waiting” may be the best strategy.
The new test could revolutionize the treatment of prostate cancer. It could save many lives and spare men with the slow-growing form of cancer from having unnecessary treatments in the future. Its manufacturer Onconome Inc., a Seattle Biomedical company, is developing the EPCA-2 test and expects the FDA to approve it by early next year.
Source: San Francisco Chronicle; Sunday, April 26, 2007; reporter Susan Brink of the Los Angeles Times
Add comment May 10th, 2007
