Prostate cancer screening: Should you get a PSA test?

Should you get a Prostate Specific Antigen test to see if you have prostate cancer? This is a question you should ask your doctor, but be prepared for a discussion — the answer isn't black-and-white.

Prostate cancer screening isn't appropriate for every man — for example, it may not be appropriate to screen men who have a short life expectancy due to other serious disease.

Some men have prostate cancer and never know it — they live long healthy lives without knowing the diagnosis, eventually dying of something unrelated to the prostate cancer. Even though one in six (17 percent) men will be diagnosed with prostate cancer in his lifetime, only one in 33 (3 percent) will die of it. This is because early treatment of prostate cancer is effective and because often, other illnesses ultimately cause death before prostate cancer.

Prostate cancer is sometimes so slow growing that it causes no signs or symptoms and may not be a threat to the length or quality of your life. It is under this scenario you may wonder about the benefits of and necessity for PSA testing.

Since PSA testing became available, the death rate from prostate cancer has decreased substantially. Despite this positive result, it's important to realize that PSA testing isn't perfect nor is it completely clear which men with prostate cancer benefit from aggressive treatment. Armed with sufficient information, you and your doctor can make a reasonable decision about PSA testing.

What is PSA?

Prostate Specific Antigen is a protein produced by both cancerous (malignant) and noncancerous (benign) prostate tissue. PSA helps liquefy the semen and enters the bloodstream at variable rates depending on the health of the prostate. Because PSA is present in both benign and cancerous prostate cells, it's not specific to only prostate cancer. However, cancer cells usually make more PSA than do benign cells, causing PSA to rise early in the course of prostate cancer. The complicating issue is that conditions other than prostate cancer also can cause PSA levels to rise, including benign enlargement of the prostate, inflammation of the prostate (prostatitis) and other less common conditions. Some prostate cancers, particularly those of an aggressive nature, may not produce much PSA, so the digital rectal examination remains an important part of evaluating the prostate.

Besides the number itself, other factors that go into interpreting PSA scores include your age, the size of your prostate and how quickly your PSA levels are changing. Because of the complexity of these relating factors, it's important that a physician experienced in interpreting PSAs evaluate your situation so that you can avoid unnecessary or inappropriate invasive testing and treatment.

Before you get a PSA test, be sure to tell your doctor if you are using finasteride for hair loss (Propecia) or finasteride for benign prostatic hypertrophy (Proscar). Studies show that finasteride can significantly decrease your measured PSA levels. Experts recommend that if you are using one of these products, your measured PSA levels should be doubled to reflect a more accurate result. Other medications that contain components of male or female hormones also can change your PSA value, so let your doctor know about all of the medicines and supplements you are using.

The prostate gland is located just below a man's bladder and surrounds the top portion of the urethra, the tube that drains urine from the bladder. The primary function of the prostate is to produce fluid in semen, the fluid produced during ejaculation.

Simple tests, not-so-simple decision

Because there are no clear answers on who should have PSA screening, consider the pros and cons of the test.

Pros of PSA screening Cons of PSA screening
PSA screening allows the early detection of prostate cancer. Cancer is easier to treat and is more likely to be cured in the earlier stages of the disease. Prostate cancer may be slow growing and never spread beyond the prostate gland.
PSA testing can be done with a simple blood test. PSA tests can't tell the difference between prostate cancer and other noncancerous prostate conditions (such as infection or noncancerous prostate enlargement). If PSA test results are questionable, more testing may be recommended, including prostate biopsies.
For some men, knowing is better than not knowing. Having the test can provide you with a certain amount of reassurance — either that you don't have prostate cancer or that you do have it and can now have it treated. You may end up with a diagnosis of prostate cancer that is not a threat to your health and doesn't require treatment.
Prostate cancer, if found early, can be successfully treated. Testing for prostate cancer may lead to unnecessary treatments. Treatment for prostate cancer can have serious risks and side effects, including urinary incontinence, erectile dysfunction or bowel dysfunction.
The number of deaths from prostate cancer has gone down since PSA testing became available. There is no clear evidence that the decrease in deaths from prostate cancer is due to early detection and treatment based on PSA or due to other factors.

Consider your age

Because prostate cancer typically grows very slowly, after age 75, or if you have another life-limiting condition, you may not need PSA testing.

Think about your risk factors for prostate cancer

Knowing the risk factors for prostate cancer can help you determine if and when you want to begin prostate cancer screening. The main risk factors include:

Age. As you get older, your risk of prostate cancer increases. After age 50, your chance of having prostate cancer increases substantially. About 70 percent of all diagnosed prostate cancers are found in men age 65 years or older.

The option to have PSA testing begins at age 50 (40 if you have risk factors) and continues until you're at the age when your life expectancy is 10 years or less. Once you reach that age, the likelihood that a prostate cancer would progress and cause problems during the remainder of your lifetime is small, so some doctors feel the test has less value then. If you have family members who lived long lives, the more reason to consider screening.

Race or ethnicity. For reasons that aren't well understood, black men have a higher risk of developing and dying of prostate cancer.
Family history. If a close family member — your father or brother — has prostate cancer, your risk of the disease is greater than that of the average American man.
Diet. A high-fat diet and obesity may increase your risk of prostate cancer.

Assess your personal preferences

How do you feel about cancer, treatment and your overall health? Consider these statements when making the decision whether to have PSA screening. Which ones seem to ring true for you? Make a checkmark by the statements you agree with.

I worry about cancer.
I would rather know that I have cancer than not know and worry about it.
I'm not concerned about prostate cancer which may never affect my health.
I don't want to undergo unnecessary testing or treatment.
I worry about my ability to maintain an active sexual life and retain urinary continence more than I worry about having prostate cancer.

How you respond to these statements may leave you leaning one way or another in your decision.


Consider the varying viewpoints: What are the recommendations?

Organization Recommendations
American Urological Association (AUA) The AUA encourages men who are in good health to have annual PSA testing starting at age 50, or at age 40 if they're in high-risk groups, such as black men or those with a father, brother or son with the disease.
American Cancer Society (ACS) The ACS recommends that doctors offer the tests to men age 50 and older who expect to live another 10 years, and test men at high risk if they're age 45 and older.
Centers for Disease Control and Prevention (CDC) The CDC considers the evidence insufficient to determine whether the benefits outweigh the harms.
U.S. Preventive Services Task Force (USPSTF) The USPSTF considers the evidence insufficient to determine whether the benefits outweigh the harms.


How does it add up?

After considering all of the pros and cons of screening, your age, general health and risk factors, your personal preferences and what the experts say, talk to your doctor and together you can make an informed decision.

There's no wrong answer when it comes to PSA testing. But it's helpful if you understand what prostate cancer screening involves, how it works and what information it provides. Based on that information, make an informed decision as to whether you want to pursue screening.


Last Updated: 01/22/2007
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