- 3 min read
The prostate health index – what is it?
Prostate specific antigen (PSA) is a protein made naturally in the prostate gland. It’s usually found in semen, but small amounts enter into the blood.
PSA is measured as nanograms of PSA per millilitre (ng/mL) or micrograms per litre (µg/L) of blood.
The Prostate Health Index (PHI) test is a newer type of PSA blood test that may be more accurate at predicting if you have prostate cancer than the PSA test or the free to total PSA test alone. It measures 3 types of PSA to produce a phi score.
The only way to diagnose prostate cancer for certain is through a biopsy which is an invasive surgical procedure. Your doctor or urologist will consider your phi score, your PSA levels, any other tests you may have had and your specific circumstances before deciding if a biopsy is necessary
What does the prostate health index check for?
PSA in the blood floats freely or is attached to blood proteins. These are called free PSA and bound PSA. Total PSA includes both free and bound PSA.
The prostate health index helps your doctor to work out if you might have prostate cancer by measuring the levels of three forms of PSA:
- PSA not bound to protein in the blood (free PSA)
- Total PSA – free and bound PSA (PSA attached to proteins in the blood)
- proPSA – this is a newly discovered protein similar to PSA, also called [−2]proPSA (p2PSA). It is called an isoform of PSA and has been shown to be more specific than PSA for prostate cancer diagnosis.
From these results a complicated phi score is calculated.
Why was the prostate health index developed?
The PSA test and free to total PSA test detect changes in the prostate, but the results of these tests can be affected by many factors and diseases, including age, infections and an enlarged prostate (benign prostate hyperplasia). The prostate health index was developed to more accurately determine if there is a chance that you may have prostate cancer. It will help your doctor work out if you need to have a prostate biopsy.
Is the prostate health index a blood test?
The prostate health index is a blood test that should be quick and relatively painless.
The blood sample is then sent to a pathology laboratory to analyse and produce the phi score. Your doctor will receive a report from the laboratory to discuss with you.
Prostate health index results – what do they mean?
Very simply, a low phi score means a low risk, a high phi score means a higher risk of prostate cancer.
Should you have the prostate health index test?
This test may predict prostate cancer better than other PSA tests, but it isn’t perfect. If you get a high-risk phi score it doesn’t always mean you have cancer, and if you get a low-risk phi score you still could be diagnosed with cancer from a biopsy.
Also, the prostate health index isn’t rebated in Australia by Medicare. So, it can’t be bulk billed. This means you will be required to pay for the full cost of the test.
Ask your doctor about the benefits of PHI testing are for you and what costs are involved.
What happens next?
Your doctor or urologist will talk to you about the next possible steps to rule out or diagnose prostate cancer, based on all your phi score, other test results and your individual risk factors. Receiving test results and discussing your next steps can be worrying and stressful. It may help to have your partner, family member or a friend with you when you talk to your doctor.
Also, don’t forget to look after yourself as you are going through this. It may be beneficial to try some relaxation techniques, look at the support services available, or reach out to a PCFA nurse if you need more information or advice.
Key points
- The prostate health index test is a newer tool that may help find prostate cancer early and reduce the number of biopsies.
- The prostate health index test calcuates a phi score from the results of total PSA, free PSA and a newer form of PSA called proPSA.
- The prostate health index test is more specific in detecting prostate cancer than other PSA tests, but it is not perfect.
- This test is not bulk-billed through Medicare, so you will have to pay upfront.
- Ask your doctor whether this test is appropriate for you.
- Your doctor or urologist will talk to you about what the test results mean for you. They will also discuss if further examinations or tests are recommended.
