Cancer screening is the process of routinely checking for cancer when there are no symptoms. Screening for prostate cancer consists of the digital rectal exam and the prostate-specific antigen (PSA) test. In a digital rectal exam, a doctor inserts a gloved finger into the rectum to feel for lumps or abnormalities in the prostate gland through the rectal wall. The PSA test is a simple blood test that determines the level of PSA – a protein excreted by the prostate gland – in the bloodstream.
The medical community is deeply split on the benefit of the PSA test. Even though the PSA test is often billed as a simple blood test that can detect cancer early and save men’s lives, there is little unquestionable evidence that the PSA test really does save lives. Opponents of the test further argue that without a clear-cut benefit, screening isn’t worth the risk because treatment carries a risk of serious side effects, such as impotence and incontinence.
What do the various medical organizations currently recommend regarding the PSA screening test?
The American Cancer Society and the American Urological Association currently recommend that health care providers:
- Offer PSA testing and digital rectal exams every year to all men beginning after age 50.
- Begin testing men at the age of 45 if they are at high risk, such as African Americans and men who have a first-degree relative (father, brother, or son) diagnosed with prostate cancer at an early age (younger than age 65).
Most U.S. government agencies—the National Cancer Institute, the Centers for Disease Control and Prevention, and the U.S. Preventive Services Task Force—do not recommend widespread screening though they agree it should be offered to those who want it.
The American Medical Association recommends simply that doctors inform their patients about the pros and cons of screening and leave the decision to them.
With medical organizations in disagreement about PSA screening, what should all men know about the current state of PSA testing and what issues should they discuss with their doctor?
- Researchers are currently questioning the threshold level of a “PSA less than 4.0” as the “normal” value below which a biopsy isn’t needed. While the screening test does pick up prostate cancer before it spreads, it also misses many aggressive cancers that occur at PSA levels well below 4.0 ng/ml.
- The PSA screen is imprecise because both benign and malignant tissue can cause elevations of PSA in the blood. In addition, certain medical conditions, such as prostatitis, urinary tract infections, and prostate enlargement, can also elevate PSA levels. On the other hand, certain drugs can interfere with PSA testing and lower reported PSA levels.
- How fast a PSA level rises over time is gaining attention as possibly more important than whether or not a PSA level is above or below 4.0 ng/ml. Studies to determine the degree of increased cancer risk and at what level to recommend biopsy are ongoing.
- Although a screening test may detect cancer, most cancers are slow growing and may never threaten the life of patients. Older patients may very well end up dying of another cause before the cancer caused any symptoms. Men in their 40s, on the other hand, who have long lives ahead of them, and during which the cancer could grow and cause them to die, may opt for regular PSA screening.
- Recent research has found that the higher a man’s PSA level is when he is younger, the more likely he is to develop prostate cancer later in life.
- Finally, also keep in mind that newer research has found that PSA screening does pick up some dangerous cancers early.
The bottom line
For a small number of patients, screening offers a chance to catch aggressive cancers before it’s too late. Therefore, for some men, the PSA screening test can be a life saver. At the same time, PSA screening subjects thousands of men every year to needless biopsies and other medical procedures that carry the risk of bleeding and infection and cause unnecessary anxiety. Further, screening leads to treatment of a lot of cancers that aren’t life threatening. In addition, the treatments can cause impotence and incontinence and seriously erode a man’s quality of life.
The issues surrounding PSA testing are conflicting and confusing. Only after the outcomes of ongoing trials are published will the role of PSA testing be further clarified. Until such time, you and your doctor must work together to make an informed decision on PSA testing. You and your doctor will review the pros and cons of the PSA screening test, your own risk factors for prostate disease, and your comfort level regarding cancer risk versus worries about treatment side effects. If you do choose to have the PSA screening test, make sure you have it along with the digital rectal exam. Having both screening tests is the most likely way not to miss a cancer.
- American Urological Association. What Patients Should Know About Prostate Screening. www.urologyhealth.org/. Accessed November 29, 2011.
- American Cancer Society. Can prostate cancer be found early? www.cancer.org/. Accessed November 29, 2011.
- U.S. Preventive Services Task Force. Screening for Prostate Cancer A Review of the Evidence for the U.S. Preventive Services Task Force www.uspreventiveservicestaskforce.org/uspstf12/. Accessed November 29, 2011.
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This information is provided by the Cleveland Clinic and is not intended to replace the medical advice of your doctor or health care provider. Please consult your health care provider for advice about a specific medical condition. This document was last reviewed on: 11/16/2011…#12804