Men age 75 and older should not be screened for prostate cancer and younger men should discuss the benefits and harms of the prostate-specific antigen (PSA) test with their clinicians before being tested, according to a new recommendation from the U.S. Preventive Services Task Force.
The recommendation and accompanying evidence summary appear in the Aug. 5 issue of the Annals of Internal Medicine.
The Task Force found evidence that screening for prostate cancer provided few health benefits, but instead, led to substantial physical harms and some psychological harms in men age 75 and older.
In men younger than 75, the panel concluded that current evidence is insufficient to assess the balance of benefits and harms of prostate cancer screening. An estimated 218,890 U.S. men were diagnosed with prostate cancer in 2007, and one in six men will be diagnosed in his lifetime, according to the U.S. Agency for Healthcare Research and Quality (AHRQ).
Screening for prostate cancer is most often performed using PSA tests and digital rectal exams. The PSA test is more likely to detect prostate cancer than the digital rectal exam, according to the panel. However, prostate cancers that are found with a PSA test take years to affect health; most prostate cancers take more than 10 years to become fatal.
Since a 75-year-old man has an average life expectancy of about 10 years and is more likely to die from other causes such as heart disease or stroke, prostate cancer screening is unlikely to help men over 75 live longer, the Task Force concluded.
For the same reasons, the panel concluded that men younger than 75 with chronic medical problems and a life expectancy of fewer than 10 years are also unlikely to benefit from screening.
There are also harms associated with prostate cancer screening, which include biopsies, unnecessary treatment and false-positive results that may lead to anxiety, according to the Task Force. Complications often result from treating prostate cancer and may include urinary incontinence and impotence. The AHRQ said that slow-growing cancers may never have affected a patient's health or well-being had they not been detected by screening.
“Because many prostate cancers grow slowly, early detection may not benefit a patient's health and in some cases may even cause harm,” said Task Force Chair Ned Calonge, MD, MPH, who is also chief medical officer for the Colorado Department of Public Health and Environment. “We encourage men younger than 75 to discuss with their clinicians the potential—but uncertain—benefits and the possible harms of getting the PSA test before they decide to be screened.”
The AHRQ said that current data show that one-third of all men in the United States older than 75 are receiving PSA testing.
Although most major medical organizations suggest that prostate cancer screening may be discontinued in men with a life expectancy of fewer than 10 years, the Task Force said it is the first group to define an explicit age cutoff above which screening is likely to be ineffective or harmful.
The results of two ongoing clinical trials—the National Cancer Institute's Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial, and the European Study of Screening for Prostate Cancer—should help to clarify the potential benefits of screening in men under the age of 75, according to the panel.