PSA Health Article

Definition

PSA stands for prostate-specific antigen. It is a protein with a sugar molecule attached that is found in prostate cells. It can be detected at a low level in the blood of all adult men.

This article discusses the blood test to measure the amount of PSA in a man's blood.

Alternative Names

Prostate-specific antigen; Prostate cancer screening test 

How the test is performed

Blood is typically drawn from a vein, usually from the inside of the elbow or the back of the hand. The site is cleaned with germ-killing medicine (antiseptic). The health care provider wraps an elastic band around the upper arm to apply pressure to the area and make the vein swell with blood.

Next, the health care provider gently inserts a needle into the vein. The blood collects into an airtight vial or tube attached to the needle. The elastic band is removed from your arm. Once the blood has been collected, the needle is removed, and the puncture site is covered to stop any bleeding.

How to prepare for the test

No special preparation is usually needed.

How the test will feel

When the needle is inserted to draw blood, some people feel moderate pain while others feel only a prick or stinging sensation. Afterward, there may be some throbbing or a bruise.

Why the test is performed

This test is done to screen for prostate cancer and other conditions. Several conditions besides cancer can cause the PSA level to rise. These include urinary tract infections, benign prostatic hyperplasia, and prostatitis.

Discuss with your doctor or health care provider whether a PSA test is appropriate for you.

Normal Values

Normal values vary with age. Older men typically have slightly higher PSA measurements than younger men. African Americans normally have slightly higher values than white men.

Normal value ranges may vary slightly among different laboratories. Talk to your doctor about the meaning of your specific test results.