Blood test
PSA Test
A PSA test is a blood test that measures a protein made by the prostate. A raised level can have several causes, including prostate problems, and sometimes prostate cancer.
Quick answer
PSA Test: what it is and what the results mean
The PSA (prostate-specific antigen) test measures a protein produced by the prostate gland in the blood. Levels can rise for several reasons, so it is a clue rather than a definite cancer test.
- Why it is done: It is used to help investigate urinary symptoms, to look into a possible prostate problem, and — after a discussion of the pros and cons — as a check for prostate cancer in men who request it.
- Understanding results: A raised PSA can be due to an enlarged prostate, infection or cancer, while a normal level does not completely rule cancer out.
What it is
The PSA (prostate-specific antigen) test measures a protein produced by the prostate gland in the blood. Levels can rise for several reasons, so it is a clue rather than a definite cancer test.
Why it is done
It is used to help investigate urinary symptoms, to look into a possible prostate problem, and — after a discussion of the pros and cons — as a check for prostate cancer in men who request it.
What to expect
It is a standard blood test from the arm. Certain activities such as vigorous exercise, ejaculation or a urine infection can temporarily raise PSA, so you may be advised to avoid these beforehand.
Understanding the results
A raised PSA can be due to an enlarged prostate, infection or cancer, while a normal level does not completely rule cancer out. Results are interpreted with your age, symptoms and examination, and may lead to further tests such as an MRI or biopsy.
Good to know
Risks and limitations
The blood test itself is very safe. The main issue is interpretation — PSA is imperfect, so it can miss some cancers and flag harmless changes, which is why the decision to test is discussed carefully first.
Education and reference only. This explains the test in general terms and is not medical advice. Always follow the specific instructions from the team arranging your test, and discuss your results with your clinician.
Answers
PSA Test: frequently asked questions
Does a high PSA mean I have cancer?
Not necessarily. A raised PSA is common and often due to an enlarged prostate or infection rather than cancer. Your clinician will interpret it with your symptoms and may arrange further tests.
Should I have a PSA test?
It is a personal decision made after discussing the benefits and limitations, as the test is imperfect. Men with symptoms, a family history or particular concerns should talk it through with their clinician.
Related tests
Other blood test investigations
Sources
Where this is drawn from
- NHS — Tests and treatments
- NICE — diagnostic guidance
- Relevant royal college / professional body
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