Monday, May 4, 2015

PSA screening by the numbers: no benefits, many harms

- Kenny Lin, MD, MPH

Previous studies found that two-thirds of men who receive prostate-specific antigen (PSA) screening for prostate cancer didn't have shared decision making with their physicians. If shared decision making occurred at all, patients were more likely to remember hearing about the advantages than the disadvantages of PSA screening, and many older men with a high probability of death within the next 9 years were screened nonetheless.

These findings, along with a Cochrane review and another systematic review (that I co-authored) which both found no pooled mortality benefits in several randomized controlled trials, led the U.S. Preventive Services Task Force to recommend against PSA-based screening for prostate cancer in 2012. Since then, the American Academy of Family Physicians and the American College of Preventive Medicine have added this service to their Choosing Wisely lists of tests and procedures that patients and physicians should question.

The Medicine By the Numbers published in the May 1st issue of American Family Physician clearly illustrates that the harms of PSA screening exceed the benefits. 1 in 5 men who received PSA screening ended up undergoing a biopsy for a false-positive test; 1 in 34 and 1 in 56 screened men, respectively, suffered erectile dysfunction or urinary incontinence as a result of prostate cancer treatment. In contrast, PSA screening prevented zero deaths from prostate cancer or all causes. In other words, no benefits.

This review begs the question of why clinicians should bother with shared decision making in most average-risk men, rather than simply telling them that this test is a bad deal.