Health Canada and the US Food and Drug Administration have approved the PCA3 test for use, however it is not widely used yet.
It will help doctors determine the need for repeat biopsy in men that have had a previous biopsy without prostate cancer.
Prostate Cancer Canada - PCA3 Test
The PCA3 Test is a urine test that detects Prostate Cancer Antigen 3 (PCA3). Prostate Cancer Antigen 3 (PCA3) is a gene that is overexpressed in prostate cancer cells. It is specific to prostate cancer cells rather than all prostate cells, and if present in urine is an indication of prostate cancer.
The PCA3 test is a more accurate test for diagnosing prostate cancer than a PSA test because benign enlargement of the prostate will not cause elevated PCA3, whereas prostate specific antigen (PSA) can be elevated due to increased prostate size (as occurs with BPH) and not just cancer.
The PCA3 test can be used to assess the need for a biopsy. If PSA is slightly elevated and PCA3 is within the normal range, the likelihood of obtaining a biopsy positive for prostate cancer is low. However, if a patient has levels of PCA3 in their urine a biopsy for prostate cancer will likely be performed.
PCA3 can also give a clue about of the aggressiveness of prostate cancer. If a patient has prostate cancer with and their PCA3 is low, the prostate cancer is more likely to be "indolent" and progress very slowly whereas if PCA3 is elevated the tumour is more likely to be aggressive.
The PCA3 test is not currently available in most clinics because it is still being optimized for widespread use.