New recommendations for prostate cancer screening
What should men do about prostate cancer screening?
For years, men were urged to get a blood test looking for prostate-specific antigen (PSA), which can be elevated by prostate cancer. Then, in 2012, the United States Preventative Services Task Force (USPSTF), a government-sponsored but independent network of national experts in disease prevention and evidence-based medicine, said that PSA testing produced more harm than good. They stopped recommending it at all.
Now, that same group has finalized a tweak on those 2012 screening guidelines. Instead of bypassing PSA entirely, men ages 55 to 69 should have a conversation with their doctor about the risks and benefits before making their own decision on whether or not to get screened.
The task force says the change was largely driven by a 2014 study in Europe (European Randomized Study of Screening for Prostate Cancer), according to a new statement and evidence review published Tuesday in the Journal of the American Medical Association (JAMA).
The European trial showed that a screening saved one prostate cancer deaths for every 1,000 men screened between ages 55 and 69. In four out of the seven countries in the European trial, screening also stopped three cases of prostate cancer from spreading for every 1,000 men screened.
Dr. Alex Krist, vice chairman of the USPSTF and a professor of family medicine and population health at Virginia Commonwealth University, says the “extended follow up of 10 plus years in these studies, which was not available in 2012, contributed heavily” to the decision to modify the recommendations.
The extended follow up showed some men’s lives would be saved if they chose to be screened between the ages of 55 to 69. Of note, the committee still finds screening for men over the age of 70 to be inappropriate -- the evidence still suggests more harm than benefit in this age group.
The committee pointed to research on some populations which may be at higher risk for prostate cancer and death from it. The incidence is 74 percent greater in African American men compared to white men. Having a family history of prostate cancer is also a known risk factor for developing the disease.
Prostate cancer is the most commonly diagnosed cancer in men and the second leading cause of cancer death in the United States. In 2018, an estimated 165,000 men will be diagnosed and 29,000 will die from prostate cancer.
The controversy over prostate cancer screening is because of the blood test developed in the late 1980s, looking for PSA.
PSA can be elevated when prostate cancer is present, but can also be elevated for a number of other reasons -- inflammation or infection -- generating a lot of false positives.
The men screened in the European trial, which drove the guideline changes, had a false positive rate of 17.8 percent. The problem with false positives is that in order to confirm prostate cancer, a patient has to undergo a biopsy.
Biopsies have side effects, such as pain, infection, and bleeding. Even when cancer is present, 20-50 percent of prostate cancers never grow, spread, or cause any harm to the patient, but doctors cannot tell which ones are harmful and which ones are harmless. Treatment also has side effects, and evidence shows that one in five men who undergo prostate surgery will have long-term urinary incontinence, and two out of three men will have long-term erectile dysfunction.
The overall message from the USPSTF, according to Krist, is that they recognize this is a complex decision.
There is no “right answer," he said.
We know a few men will benefit from screening. We know many men will have harm from screening. It depends on what these men value, and having a conversation with their doctor is an important process of whether screening is right for them.
The USPSTF recognizes these recommendations are likely to be confusing for both patients and medical providers. Therefore, they have set up a user-friendly website for those interested in educating themselves about prostate cancer and the new recommendations: https://screeningforprostatecancer.org/
David J. Kim, MD is a final year Emergency Medicine resident at the University of California, Los Angeles, working with the ABC News Medical Unit in New York.
