Wednesday, March 30, 2011

Prostate-specific antigen screening is not effective

According to the Cochrane for Clinicians summary in the the April 1st issue of AFP, a review of five randomized, controlled trials with more than 340,000 participants found no statistically significant effect of prostate-specific antigen (PSA) screening on mortality from prostate cancer. An independent meta-analysis published last year in BMJ also concluded that routine screening had no measurable health benefits and could not be recommended. On the other side of the ledger, Drs. Nathan Hitzeman and Michael Molina point out that

Established harms of PSA testing include excessive worry over false-positive results and morbidity from interventions, including infection, bleeding, pain, long-term sexual dysfunction, and urinary incontinence. A recent analysis showed that PSA testing does not attain the likelihood ratios necessary to qualify as a screening test, regardless of the cutoff value used. The inventor of the PSA test said the test's popularity has caused “a hugely expensive public health disaster.”

Despite the preponderance of evidence that this test is not effective, and frequently results in harm to patients, data from the National Health Interview Survey published earlier this week in the Journal of Clinical Oncology demonstrate that PSA screening is becoming more common in the U.S., not less. 45 percent of men age 70 to 74 years, and 25 percent of men age 85 years or older, report being screened.

The U.S. Preventive Services Task Force and the AAFP recommend against screening for prostate cancer in men age 75 years or older, due to their limited life expectancies and the high likelihood of death from a cause other than prostate cancer. Nonetheless, clinical practice remains far out of step with the evidence. What approach do you take to discussing prostate cancer screening with your patients?