Finding and Diagnosing Prostate Cancer

Tests to help find and diagnose prostate cancer

PSA (prostate-specific antigen) blood test. A normal PSA is less than 4.0 ng/mL. If the PSA level is greater, it is more likely that prostate cancer is present. However, there are other conditions that can raise the PSA. Men with a PSA level between 4.0 and 10.0 ng/mL have about a 25 percent chance of having prostate cancer. If the PSA level is greater than 10.0ng/mL, the chance of having prostate cancer is over 50 percent. If you have a high PSA, a doctor will look at other factors such as age, race, and family history, and also rule out any other possible conditions causing the elevated PSA. If other conditions have been ruled out, the doctor will recommend a prostate biopsy.


Digital rectal exam (DRE): A digital rectal exam not as effective as the PSA blood test in detecting prostate cancer. However, it is still a good way to identify any abnormal nodules that may be present on the prostate gland. It can also sometimes find prostate cancer in men who have a normal PSA level.

PHI. The PHI test measures total PSA as well as two special forms of the protein: free PSA (fPSA), and pro2PSA. tPSA includes all types of PSA circulating in the bloodstream, whether free or bound to other proteins; fPSA is PSA that circulates as a free protein, unattached to any other proteins; and pro2PSA is a form of PSA that is highly expressed in prostate cancer tissue and is associated with more aggressive disease. Using these three values, a PHI score is calculated. The PHI score provides a more accurate measurement to assess prostate cancer risk than any known PSA-based marker alone. And by using pro2PSA, the PHI test can detect more aggressive cancers. This reduces the harm many men experience with overtreatment.

PCA3. A PCA3 (prostate cancer gene 3) test is a simple urine test used to predict the likelihood of prostate cancer. Specifically, it is an additional tool used to determine whether a prostate biopsy is necessary. The PCA3 is specific for prostate cancer as the prostate cancer gene is only produced by prostate cancer cells. As for what the PCA3 score means, the higher the PCA3 score, the more likely that prostate cancer will be found in the prostate biopsy. Therefore, a prostate biopsy is recommended. If the PCA3 score is low, a prostate biopsy may be unnecessary or at least delayed for some time.

4k Score test. The 4Kscore test is a simple blood test that detects high risk, aggressive prostate cancer. It measures four prostate protein (prostate-specific kallikreins) levels in your blood including total PSA, free PSA, intact PSA, and human kallikrein 2 (hK2). The results are combined in an algorithm with patient age, digital rectal exam and prior negative biopsy to give physicians a personal score for each patient.