Active Surveillance for Prostate Cancer Patients

From Medscape

May 12, 2008 — The urine test for the PCA3 gene, already marketed for use in diagnosing prostate cancer, could also be useful in prognostication. It might have clinical application in selecting men with low-grade and low-volume tumors who would be suitable candidates for active surveillance, say researchers writing in the May issue of the Journal of Urology.
The PCA3 urine test, marketed in Europe by Gen-Probe, has been shown in previous studies to be more accurate in diagnosing early prostate cancer than serum levels of prostate-specific antigen (PSA).

I usually use the PCA 3 test for men who have had a negative biopsy and we are considering performing a second one. I usualy use it for men with high grade PIN after one biopsy. If the PCA 3 is positive, I usually perform a second biopsy. I have not looked at my data to see if the above correlation exists, but that would be interesting.
I also am not sure if you can use PCA 3 tests that are taken a few months apart to mean anything. For example, would a rise in PCA 3 be expected if a man develops cancer or the cancer is growing?