Prostate cancer is common. About 200 in every 1,000 Australian men will be told they have prostate cancer by the age of 85. But the chance of dying from it is much lower: around 18 in 1,000 cases.

Prostate-specific antigen (PSA) blood testing remains the most widely used test to detect prostate cancer – but it’s far from perfect.

The first update to Australia’s PSA testing guidelines in a decade now recommends men aged 50 to 69 consider having a PSA test every two years.

Those aged 45 to 50 and over 70 may be eligible for a test but should talk to their GP about the potential risks and benefits, and their individual circumstances.

Rectal examinations are not routinely recommended alongside PSA tests.

How does PSA testing work?

PSA is a protein made by the prostate gland. It liquefies the ejaculate in semen so sperm can swim. A small amount leaks into the bloodstream, and a PSA test measures how much.

Men’s prostates produce different baseline levels of PSA. This is partly due to genes, which explain up to 16% of the differences in PSA between men.

Total PSA greater than 3.0 nanograms per milliliter (ng/mL) is considered an elevated PSA level in the guidelines for men 50 to 69.

PSA is a prostate test, not a cancer test. Any breakdown in the cells of the prostate can make it leak. A raised result could mean prostate cancer. Or it could mean a benign (non-cancerous) enlarged prostate, an inflamed prostate, or an infection.

The point of the test is to catch a dangerous cancer while it is still inside the prostate and still curable. But some cancers produce very little PSA, so a normal result cannot completely rule cancer out. And the PSA test cannot........

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