PCA3 is a specific gene for prostate cancer
It is present at much higher levels in prostate cancer tissue than in normal prostate tissue.
Unlike prostate specific antigen (PSA), PCA3 is only produced by cancer cells of the prostate and is not affected by the size of the prostate. Therefore, it discriminates better than PSA between prostate cancer cells and non-cancerous benign prostate diseases such as benign prostatic hyperplasia (BPH) or prostatitis (infection of the prostate). Therefore, PCA3 is a good tumor marker for the detection of prostate cancer that allows to decide if a prostate biopsy is really necessary.
What does the PCA3 test indicate?
The PCA3 test is a simple test. After a rectal exam, cancer cells with high levels of PCA3 break off from the prostate and pass into the urine. A urine sample is then collected and sent to a laboratory to determine the PCA3 score.
The PCA3 test is considered positive from a value of 35 and has a sensitivity of 68% and a specificity of 78%.
The results will determine:
The need to perform aa prostate biopsy
The higher the PCA3 score, the more likely it is that the biopsy will be positive, while the lower the PCA3 score, the more likely that the biopsy will be negative.
In this way, the PCA3 assay can help to avoid in many cases the need for a first biopsy, with the discomfort and possible complications such as pain, bleeding and infections.
The aggressiveness of cancer
The higher the PCA3 score, the greater the likelihood that the cancer is aggressive, in which case treatment such as surgery or radiation therapy is more advisable. If the prostate cancer is not aggressive, and an active surveillance plan is being followed, the PCA3 test can be repeated every 3-6 months. A substantial increase in PCA3 levels may indicate progression of the cancer.
- Prostate specific antigen (PSA): prostate cancer screening
- New genetic markers implicated in the prognosis of prostate cancer
- Early detection of prostate cancer
- Transrectal prostate biopsy