The PSA test is a blood test that can detect the early signs of an enlarged prostate. It is the most common initial test for men who are worried about prostate cancer.
The test, which can be done by your doctor, measures the level of prostate-specific antigen (PSA) in your blood.
PSA is a protein made only by the prostate gland. Some of it will leak into your blood, and the amount depends on your age and the health of your prostate.
The amount of PSA in your blood is measured in nanograms of PSA per millilitre of blood (ng/ml). PSA levels can range from less than 1ng/ml to hundreds of ng/ml.
There are well-known issues with the accuracy of the PSA test and potential harmful consequences, which is why there is currently no national screening programme for prostate cancer in the UK.
Instead, all men over the age of 50 can access quality information about the PSA test and discuss the option of having a free test with their GP as part of a scheme called the prostate cancer risk management programme (PCRMP).
Under PCRMP, your GP will be expected to discuss with you the benefits, limitations, and risks of the PSA test to help you decide whether or not to have it.
You should also be given a leaflet about PSA testing for prostate cancer. The leaflet provides similar, but more detailed, information to what you'll find on this page.
Men are at higher risk of prostate cancer if they have a family history of prostate cancer, are of black ethnic origin, or are overweight or obese.
If you are worried about prostate cancer, you should talk to your GP. Read more about prostate cancer , including the symptoms of prostate cancer and treatments for prostate cancer , in our Health A-Z section.
If you're having a PSA test, you should not have:
Each of these may give an inaccurate PSA reading.
There are usually three main options after a PSA test.
A normal PSA level If your PSA level is not raised, you are unlikely to have cancer. No immediate action is needed, although you may have further PSA tests in the future. However, the PSA test doesn't always pick up prostate cancer.
A slightly raised PSA level Three out of four men with a raised PSA level will not have prostate cancer. If your PSA level is slightly higher than normal, you probably don't have cancer, but you might need more PSA tests.
A raised PSA level One in four men with a raised PSA level will have cancer. The higher the level of PSA, the more likely it is to be a sign of cancer. If your PSA level is definitely raised, your doctor will arrange for you to see a specialist for further tests to find out if you have prostate cancer.
A PSA test alone cannot tell you whether you have prostate cancer. Your doctor may also perform a digital rectal examination (DRE) . This is an examination of the prostate gland, during which the doctor will insert a gloved finger into your rectum.
The DRE checks for signs of prostate cancer, such as the prostate gland feeling hard. However, a gland that feels normal does not necessarily mean you don't have cancer.
Many early cancers may not be detected by a DRE, so a DRE is not recommended as a substitute for the PSA test.
Your doctor will also consider your age, any family history of prostate cancer, your ethnic background, and any previous PSA test results.
In some cases, extra PSA tests may help make the situation clearer or show any changes.
If your PSA level is raised, a biopsy, which involves taking tissue samples from the prostate gland, may be needed to check if you have cancer.
Prostate biopsies can miss some cancers. One in five cancers are missed at prostate biopsy. You may not know for sure that you don't have cancer after a clear result, and biopsies sometimes have to be repeated.
Biopsies can sometimes cause complications. The most common is bleeding followed by infection. Most men experience blood in the urine and blood in the sperm after a biopsy. Antibiotics will be given to prevent infections.
If early prostate cancer is found, the treatment you receive will depend on your individual circumstances. The type and size of the cancer and your general health are among factors that will be considered when deciding on the right type of treatment.
Most types of treatment, such as surgery and radiotherapy, come with serious side effects, including erection, fertility, and bladder problems.
Read more about treating prostate cancer .
You should talk to your consultant about the benefits and risks of any treatment before you begin.
Important: Our website provides useful information but is not a substitute for medical advice. You should always seek the advice of your doctor when making decisions about your health.