American College of Preventive Medicine Does Not Recommend Prostate Cancer Screening With DRE, PSA

February 5, 2008 — Information is not adequate to recommend screening men for prostate cancer with digital rectal examination or measurement of prostate-specific antigen (PSA), according to a position statement by the American College of Preventive Medicine (ACPM) published in the February issue of the American Journal of Preventive Medicine.

"Prostate cancer is the leading cancer in U.S. men, and the third leading cause of cancer deaths," write Lionel S. Lim, MD, MPH, FACP, from the Griffin Hospital (Lim) in Derby, Connecticut, and colleagues from the ACPM Prevention Practice Committee. "Principal screening tests for detection of asymptomatic prostate cancer include digital rectal examination (DRE) and measurement of the serum tumor marker, prostate-specific antigen (PSA). There are risks and benefits associated with prostate cancer screening."

Although randomized controlled trials (RCTs) of screening for prostate cancer with digital rectal examination and PSA are limited to 2 previously published studies, 2 additional large-scale RCTs are currently ongoing. This review evaluated the efficacy of digital rectal examination and PSA for prostate cancer screening based on medical literature published before July 2007.

In clinical practice, applications of PSA screening tests include (1) a PSA cutoff value of 4 ng/mL, (2) age-specific PSA, (3) PSA velocity, (4) PSA density, and (5) percent free PSA.

Although prostate cancer screening can diagnose the disease in its early stages, thereby potentially decreasing morbidity and mortality, the benefits of prostate cancer screening remain unproved, pending findings from RCTs currently in progress. At present, no conclusive data demonstrate that early screening, detection, and treatment reduce mortality.

Other suggested potential benefits of screening include reassurance of being at low risk for prostate cancer and the fact that PSA can be easily obtained with a simple blood test and is widely available.

Potential harms of screening for prostate cancer include potential adverse health effects associated with false-positive and negative results and adverse effects of treatment. Other limitations of screening are that a survival benefit from prostate cancer screening has not been proved in rigorous trials.

A false-positive result from prostate cancer screening could lead to increased anxiety, as well as the discomfort and possible complications of biopsy, such as pain, hematospermia, hematuria, or infection. Conversely, false reassurance from a false-negative test could delay the diagnosis of prostate cancer.

Even for true-positive screening results, there may be harms because prostate cancer may be slow growing, never advancing, or progress to cause significant disease or death and because of short-term and long-term adverse effects of treatment, such as pain, urinary incontinence, and impotence.

"The American College of Preventive Medicine concludes that there is insufficient evidence to recommend routine population screening with DRE or PSA," the review authors write. "Clinicians caring for men, especially African-American men and those with positive family histories, should provide information about potential benefits and risks of prostate cancer screening, and the limitations of current evidence for screening, in order to maximize informed decision making."

The ACPM agrees with the American College of Physicians that informed discussion about screening should take place annually, during the routine periodic examination, or in response to a request by the patient.

The American Urological Association recommends that men who are 50 years and older and who have an estimated life expectancy of more than 10 years should be offered PSA screening. The American Cancer Society recommends that men who are 50 years and older and who have a life expectancy of more than 10 years should be offered both DRE and PSA screening. The Canadian Task Force on Preventive Health Care recommends against routine screening with PSA.

"The effectiveness of prostate cancer screening is questionable in elderly men with competing comorbidities and men with life expectancies of less than 10 years," the review authors note. "Ultimately, a man should be allowed to make his own choice about screening, in consultation with his physician, taking into consideration personal preferences and life expectancy. If the patient prefers to defer to the clinician or is unable to make a decision regarding screening, then testing should not be offered as long as the patient understands the benefits, potential limitations, and adverse effects associated with screening."

In men at average risk for prostate cancer, the usual age for screening is between 50 and 70 years. However, those who are at high risk might benefit from earlier screening starting at age 45 years, and higher-risk men with 2 or more first-degree relatives with prostate cancer before age 65 years might begin screening at age 40 years.

"Granted that prostate cancer is more likely to be found in high-risk men, issues pertaining to tumor grade have yet to be resolved (that is, optimal grade of tumor that a screening test should detect to confer a benefit in survival or morbidity), and there is still no evidence establishing effectiveness of screening in high-risk men," the review authors conclude. "In the meantime, further studies are needed to establish the efficacy and optimal age at which prostate cancer screening should be initiated in these high-risk population groups."

According to the American Cancer Society, no major scientific or medical organization supports routine testing for prostate cancer at this time.

The review authors have disclosed no relevant financial relationships.

Am J Prev Med. 2008;34:164-170.