Not in the normal realm of advanced prostate cancer, but important for the prostate cancer world is the news that the FDA has approved a new screening test for prostate cancer.

The currently used screening tool, the PSA has only a 55% accuracy rate and as recently run into serious trouble with The U.S. Preventive Service Taskforce (USPSTF). The task force has issued a new recommendation lowering the PSA screening rating from an “I” or inconclusive to a “D” recommending against the service.
An occasionally used, but better screening tool is the free PSA/The total PSA. However, this screening method is only 65% accurate, again not terribly accurate.

Yesterday, the FDA approved an alternate screening tool called the “phi.” The phi boasts an accuracy rate of 75%, an improvement over both the PSA and the PSA/free PSA.


What is the phi?

The phi is a blood test that looks for the presence of a truncated proPSA (p2PSA) molecule in the blood. If this molecule is present it then combines this finding with the free and post PSA results in the same blood sample. The end result is a phi score.

If the phi score is:

0-22.9 there is a low risk of prostate cancer (8.4%).
23-44.9 there is a moderate risk of prostate cancer (21%).
>45 there is a high risk of prostate cancer (44%).

Men in the high risk and possibly the moderate risk range can then discuss the merits of having a prostate biopsy.

The hope is that by using this newly approved test the number of unnecessary biopsies will be reduced.
The phi test will not become available in the United States until the end of 2012.

Joel T. Nowak, M.A., M.S.W.