What Does a High PSA Mean?

PSA, prostate specific antigen, is a protein made by the prostate gland and normally present in small amounts in blood. A raised PSA means the prostate is releasing more than usual. That happens for many reasons. Most men with a mildly or moderately raised PSA do not have prostate cancer, which is the single most important thing to know before the next appointment.

It is a prostate specific test, not a cancer specific one. That distinction explains almost everything about how it is used.

What counts as raised#

There is no universal cut-off, because PSA rises naturally as the prostate enlarges with age. Widely used age related guides are about:

The same value in micrograms per liter is identical, so ng/mL and mcg/L read the same. The trend over time, sometimes called PSA velocity, often carries more information than any single number.

Why it goes up without cancer#

Benign prostatic enlargement is the most common reason by a wide margin. Beyond that, prostatitis and urinary infection can raise PSA substantially and for weeks afterwards. Ejaculation in the previous two days, long distance cycling, a recent catheter, a recent digital rectal examination and any prostate procedure all lift it temporarily.

Some medicines lower it instead. Finasteride and dutasteride, used for prostate enlargement and hair loss, roughly halve PSA, so the reading has to be interpreted with that in mind.

What happens next#

A first raised PSA in a man without symptoms is usually repeated after a few weeks under better conditions. If it remains raised, the next steps usually involve an examination of the prostate, a urine test, and increasingly an MRI scan of the prostate before any biopsy is considered.

A biopsy is not the automatic next step it once was. MRI first pathways were introduced precisely because too many men were being biopsied for changes that turned out to be benign, and biopsy carries its own small risks of infection and bleeding.

The honest limitations#

PSA testing finds some cancers early and saves some lives. It also finds slow growing cancers that would never have caused harm, leading to treatment with real side effects. That trade-off is why screening policies differ between countries and why the decision to test at all is meant to be a conversation rather than a routine tick box.

If you have a family history of prostate cancer, or are of African or Caribbean ancestry, your baseline risk is higher and that conversation shifts accordingly.

Putting it in context#

A PSA result belongs with your age, symptoms, examination and previous values, not on its own. If you are trying to make sense of a wider set of results from the same appointment, the guide to understanding your blood test results explains how the report is read as a whole.