What is the PCA3 test?
The PCA3 (uPM3) is a urine test that predicts cancer in prostate biopsy with better accuracy than prostate specific antigen (PSA). Patients who receive the PCA3 test undergo an “attentive” digital rectal prostate examination by a urologist, a standard procedure in prostate cancer detection. This exam causes cells from the patient's prostate to be shed into the urine, and the urine sample, containing the released cells, is sent to a laboratory to be tested for genetic expression of the PCA3 gene. If the sample is positive for PCA3, then the patient has a significant likelihood of having prostate cancer.
The PCA3 test is available commercially but has not been evaluated by the FDA as a test for prostate cancer. It may provide guidance as to who should undergo a biopsy.
Can other tests identify prostate cancer?
New scanning technologies, such as color Doppler ultrasound and endorectal MRI with spectroscopy, have been demonstrated to locate significant tumors within the prostate. These may can be useful for targeting a biopsy but they are not definitive for diagnosing cancer. These are discussed in the Understanding Your Diagnosis section under Diagnostic Imaging.
Page updated 8/1/11