PSA Test

Man having his blood drawn by healthcare provider.

The PSA (prostate specific antigen) test is a blood test. It can help find prostate cancer. PSA is a substance found in semen. It’s made by the prostate. It's normal for some PSA to leak from the prostate into the blood. But sometimes, changes in the prostate cause more than a normal amount of PSA in the blood. The PSA test measures the amount of PSA in the blood. If the test shows high blood level of PSA, other tests are needed to help find the cause.

Possible causes of increased PSA

Many things can cause extra PSA to enter the blood, such as:

  • Enlarged prostate not due to cancer (benign prostatic hyperplasia or BPH)

  • Prostate biopsy

  • Prostate cancer

  • Prostate infection (prostatitis)

  • Prostate massage

  • Recent ejaculation

Why a PSA test is done

A PSA test can be done to check for prostate cancer. But this test by itself can’t tell for sure whether a man has prostate cancer. And not all healthcare providers agree whether all men should have PSA tests to screen for prostate cancer.

The American Cancer Society and many other organizations advise men talk with their provider to decide if prostate cancer screening is right for them. (Screening is testing for cancer in people who have no signs of it.) Talk with your provider about the PSA test starting around age 50, or earlier if you’re at higher risk. You're at higher risk if you have a family history of prostate cancer or are African American.

A PSA test may also be done if a problem is found during a routine prostate exam. And it may be done if you have symptoms that suggest that you have a prostate problem. You may need a PSA if you have symptoms such as:

  • Pain when urinating

  • Straining to urinate

  • Needing to urinate more often

  • Seeing blood in your urine

  • Waking often to urinate at night

How a PSA test is done

Before or after a PSA test, you may have a digital rectal exam (DRE). For this exam, the healthcare provider puts a greased, gloved finger into your rectum to feel the prostate. You’ll also have your blood drawn for the PSA test. The test may be done in the provider’s office. Or it may be at a lab, clinic, or hospital. Blood is taken from your arm and sent to a lab to be tested.

Getting your results

The time it takes to get your test results varies. Your healthcare provider can tell you when to expect your results. You and your provider will discuss the results together. A normal range for your PSA depends on things such as:

  • Your age

  • The size of your prostate

  • Your risk factors for cancer

  • Your symptoms

  • Past PSA test results

All of these things are taken into account when your PSA tests numbers are checked.