PCA3 Test

 

How is the PCA3 test performed?

The PCA3 test is performed on a urine sample. Just prior to collecting the urine sample, the physician performs a digital rectal exam (DRE) to release cells from the prostate.

The PCA3 test measures PCA3 mRNA and PSA mRNA in the urine sample (mRNA, which stands for messenger RNA, is a molecule that contains genetic information to make a protein). The PSA mRNA measurement ensures that prostate cells were collected in the sample and also provides a means to normalize the PCA3 amount. The result is reported as a ratio of PCA3 mRNA to PSA mRNA. The measured PCA3/PSA ratios allow us to establish the risk of having prostate cancer. Since PCA3 can be over-expressed in cancer cells compared to normal cells1, samples with high PCA3/PSA ratios give a high risk result. Samples with PCA3/PSA ratios below a certain amount are low risk.

1Hessles, et al. (2003) European Urology, 44:1.