Prostate Health Index (phi)

Information for Healthcare Providers

The Prostate Health Index (phi) test is an FDA-approved blood test that can help distinguish prostate cancer from benign prostatic conditions.

The Prostate Health Index (phi) test is an FDA-approved that combines scores from three blood tests (PSA, PSA Free, and p2PSA) to create a phi score. The phi score provides more information about what elevated PSA levels might mean and the probability of finding prostate cancer on biopsy. It’s a powerful test in differentiating between elevated PSA levels due to benign conditions and prostate cancer.

Healthcare providers should keep in mind that results from the phi test should not be interpreted as absolute evidence of the presence or absence of malignant disease.

Rather, the phi score should be used in combination with other clinical information to create an informed decision about whether or not to move forward with a prostate biopsy.

phi test benefits

The phi test combines results from the following:

  • PSA: PSA (prostate specific antigen) is a protein that is produced by prostate cells. In this case, PSA represents Total PSA, which is the PSA that is bound to other proteins as well as PSA that is found on its own in the blood. The PSA that is found on its own is known as PSA Free. The PSA test alone has 55% diagnostic accuracy.
  • Percentage Free PSA (% fPSA): The PSA that is found on its own is known as PSA Free. The % fPSA is the PSA Free divided by the PSA bound to other proteins (and the approximate percentage that this constitutes). The % fPSA has 65% diagnostic accuracy.
  • p2PSA: This is a test that measures the amount of -2 pro PSA in the blood, a special type of free floating (unbound to other proteins) PSA which has been shown in research to be present in higher concentration when cancer is present (as opposed to Total PSA, which can be elevated in the presence of benign conditions such as an enlarged prostate or a prostate infection). The p2PSA has 70% diagnostic accuracy, according to a study published in Scientific Reports.

The phi score is a special calculation between the 3 markers above (PSA, PSA Free, and p2PSA). This calculation can be used to create find a man’s probability of having prostate cancer and can help inform future decisions, like whether or not to proceed with a prostate biopsy. The diagnostic accuracy of phi is 75%.

How to Order the phi test

Healthcare providers interested in ordering the Prostate health index (phi) for patients should visit or call 1-(800)-526-3821.

Provider FAQs about phi test

Who should consider a phi test?

Good candidates for the FDA-approved blood test, Prostate health index (phi), are men with abnormal digital rectal exam (DRE), a PSA between 2-10 ng/ml, a low risk (Gleason 3+3=6) prostate biopsy, or men with a previously negative prostate biopsy.

What do phi test results mean?

The Beckman Coulter phi range for probability of prostate cancer risk upon biopsy are:

  • phi between 0-26.9: 9.8% risk
  • phi between 27-35.9: 16.8% risk
  • phi between 36-54.9: 33.3% risk
  • phi greater than 55: 50.1% risk

View a results report to get a more comprehensive look at phi test results.

Medical Studies Involving phi Test

Beyond PSA: The Role of Prostate Health Index (phi)

Literature data showed that phi had good diagnostic performance to identify clinically significant (cs) PCa, suggesting that it could be a useful tool for personalized treatment decision-making. In this review, phi potentialities, limitations, and comparisons with other blood- and urinary-based tests were explored.

Prostate Health Index and Prostate Health Index Density as Diagnostic Tools for Improved Prostate Cancer Detection

The objective of the present study was to evaluate the diagnostic potential of p2PSA, %p2PSA, phi, and phi density (PHID) as independent biomarkers and in combination with other demographic and clinical parameters, to predict overall and clinically significant PCa. The ability of p2PSA and its derivatives to discriminate HGPIN at biopsy was evaluated.

The prostate health index selectively identifies clinically significant prostate cancer

We investigate whether phi improves specificity for detecting clinically significant prostate cancer and can help reduce prostate cancer over diagnosis. The test outperforms its individual components of total, free and [-2]proPSA for the identification of clinically significant prostate cancer. Phi may be useful as part of a multivariable approach to reduce prostate biopsies and over […]