Computer tomography and magnetic resonance imaging often fail to detect the spread of prostate cancer. That leads to unnecessary surgery, because once the cancer has spread beyond the prostate, the otherwise effective treatment of surgically removing the gland has little benefit and causes undue stress. After metastasis, other measures are required, such as radiation treatment.
Now, scientists at Columbia-Presbyterian Medical Center in New York have developed the first blood test that can detect the metastasis of prostate tumors. An existing blood test, called PSA, can screen for prostate cancer--but not its location. The new test, dubbed RT-PCR, detects prostate cells in the blood--a sure sign that the cancer has spread. Aaron E. Katz, assistant professor of urology, says the test is at least 80% accurate, while MRI and CT fare no better than 60%. Abbott Laboratories and several other drug companies are interested in commercializing the method.