How is Prostate Cancer Diagnosed?


Screening is when you test for a disease even if you have no symptoms. Health care providers use the prostate specific antigen (PSA) test and digital rectal examination (DRE), to screen for prostate cancer. They advise both for early detection. There is debate on how often men should have a PSA test. Abnormality in either test is usually not due to cancer, but to other common conditions.

The American Urological Association (AUA) recommends talking with your health care provider about if you should be screened and when. To find out if prostate cancer screening is right for you, take our Risk Assessment Test. Take your results to your next appointment and talk with your health care provider about the benefits and risks of screening. There are two types of screenings, they are:

PSA Test

The prostate-specific antigen (PSA) blood test is the main method for screening for prostate cancer. This blood test measures the level of prostate-specific antigen (PSA) in the blood. PSA is a protein made only by the prostate gland. The PSA test can be done in a lab, hospital or health care provider's office. There is no special preparation. The PSA test should come before the health care provider does a DRE. Ejaculation can raise the PSA level for 24 to 48 hours. So the patient should not ejaculate for two days before a PSA test.

Very little PSA is found in the blood of a man with a healthy prostate. A low PSA is better for prostate health. A rapid rise in PSA may be a sign that something is wrong. One possible cause of a high PSA level is benign (non-cancer) enlargement of the prostate. Inflammation of the prostate, called prostatitis is one more common cause of high PSA levels. Prostate cancer is the most serious cause of a high PSA result. Talk with your health care provider about whether the PSA test is right for you. If you decide to get tested, be sure to talk about changes in your PSA score with your provider.


Digital Rectal Exam (DRE)
Digital Rectal Exam (DRE)
Alan Hoofring (Illustrator), National Cancer Institute

The digital rectal examination (DRE) is done with the man bending over or lying curled on his side. The health care provider puts a lubricated gloved finger into the rectum. The health care provider will feel the prostate. They will be looking for abnormal shape or thickness in the prostate. The DRE can help your health care provider find prostate problems.

Who Should Get Screened?

Talk to your healthcare provider about prostate cancer screening if you are a man:

  • Between 55–69 years old
  • African–American
  • Have a family history of prostate cancer

What are the benefits and risks of screening?

The PSA test may put your mind at ease. It may find prostate cancer early, before it spreads. Early treatment helps slow the spread of cancer. This may help some men live longer.

The risks of a PSA test are that it may miss detecting cancer (a "false negative"). Or the test may be a "false positive," suggesting something is wrong. This may lead to a biospy that isn't needed. The test might also detect very slow growing cancer that will never cause problems.

DRE is not expensive. It is safe and easy to do. But the DRE by itself cannot detect early cancer. It should always be done with a PSA test.


Transrectal prostate biopsy
Transrectal prostate biopsy
© 2005 Terese Winslow, U.S. Govt. has certain rights

Biopsy is the only way to find out for sure if you have prostate cancer. The decision to have one should be based on PSA and DRE results. It should consider such things as family history of prostate cancer, ethnicity, biopsy history, and other health factors.

Prostate biopsy is best done with ultrasound and a probe. You may get an enema and take antibiotics before the biopsy. You will lay on your side and the probe goes into the rectum.

First, your health care provider takes a picture of the prostate using ultrasound. Your health care provider will note the prostate gland's size, shape and any abnormalities. The most common abnormalities are shadows, which might be prostate cancer. But not all prostate cancers can be seen. And not all shadows are cancer.

The prostate gland is then anesthetized through a needle passed through the probe. Your health care provider will do the biopsy. The health care provider removes a slice of prostate tissue about ¾ inch long and 1/16 inch wide. Usually 10 or more biopsies are performed. The number depends on the size of the prostate gland, PSA test results, and past biopsies.

The biopsy takes 10 to 20 minutes. A pathologist (a health care provider who specializes in tissue) studies the biopsy tissue. The pathologist sees if there is cancer.

After a biopsy, you may have blood in the ejaculate, urine and stool. This stops within a few days for urine and a few weeks for semen. About 1 to 2% of patients have high fever. You will need to take an antibiotic for at least 48 hours after the biopsy.