Test Overview
A prostate-specific antigen (PSA) test measures the amount of prostate-specific antigen, Opens dialog in the blood. PSA is released into the blood by the prostate, Opens dialog, which is part of the male reproductive system. Healthy people have low amounts of PSA in the blood. The amount of PSA in the blood normally increases as the prostate enlarges with age. PSA may increase because of inflammation of the prostate (prostatitis, Opens dialog) or prostate cancer, Opens dialog. An injury, a digital rectal exam, or sexual activity (ejaculation) may also briefly raise PSA levels.
Do not ejaculate during the 2 days before your PSA blood test, either during sex or masturbation. Talk to your doctor about any concerns you have regarding the need for the test, its risks, how it will be done, or what the results will mean.
A health professional uses a needle to take a blood sample, usually from the arm.
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When a blood sample is taken, you may feel nothing at all from the needle. Or you might feel a quick sting or pinch.
There is very little chance of having a problem from this test. When a blood sample is taken, a small bruise may form at the site.
Each lab has a different range for what's normal. Your lab report should show the range that your lab uses for each test. The normal range is just a guide. Your doctor will also look at your results based on your age, health, and other factors. A value that isn't in the normal range may still be normal for you.
Normal
Because normal PSA levels seem to increase with age, age-specific ranges may be used. But the use of age-specific ranges is controversial, and some doctors prefer to use one range for all ages. For this reason, it is important to discuss your test results with your doctor.
A PSA level within the normal ranges does not mean that prostate cancer is not present. Some men who have prostate cancer have normal PSA levels.
High values
High levels don't always mean that prostate cancer is present. PSA levels may be high if the prostate gland is enlarged (benign prostatic hyperplasia, or BPH, Opens dialog) or inflamed (prostatitis, Opens dialog).
If your PSA level is high, your doctor may refer you to a urologist. What tests come next will depend on your overall health, your chances of having prostate cancer, and your feelings about having tests and treatments. You may have a repeat PSA test, an MRI, or tests that look at your risk for prostate cancer. Or you may be scheduled for a prostate biopsy.
