March 9 (UPI) -- Researchers found a single PSA blood test had no benefit in reducing prostate caner in a large study conducted in Britain.
The prostate-specific antigen test increased detection of low-risk prostate cancer but there was no significant difference in mortality after 10 years, according to findings published this weeky in the Journal of the American Medical Association.
Researchers studied 419,582 men from 573 primary care practices in the Britain between 2001 and March 2016. Current policy in the United Kingdom doesn't advocate screening.
In the United States, the U.S. Preventive Services Task Force recommends against the screening for men who do not have symptoms because of false positives or false negatives, as well as anxiety and unnecessary biopsies. The task force is part of Centers for Disease Control and Prevention.
Some doctors and professional organizations encouraged yearly PSA screening for men beginning at age 50 until 2008 when recommendations were changed, according to the National Cancer Institute.
In the study, 189,386 men were invited to a PSA screening clinic to receive a single PSA test. The other 219,419, as a control group, were not screened.
"Although longer-term follow-up is under way, the findings do not support single PSA testing for population-based screening," the researchers wrote.
Among those receiving the PSA, 4.3 percent were diagnosed with prostate cancer, and 549 men, or 0.30 per 1,000 persons, died. And for those not receiving the screening, 3.6 percent had the prostate cancer diagnosis and 647 of them died within 10 years, or 0.31 per 1,000.
"A key question is whether the findings from the CAP trial should swing the pendulum further in the direction of not offering screening PSA tests," Dr. Michael J. Barry, professor of medicine at Harvard Medical School, wrote in an accompanying editorial in the journal.
Barry wrote that a single PSA screen in a population of men aged 50 to 59 years is ineffective and because of the higher risk for a diagnosis the extra test "likely does more harm than good."
"In a biological sense, of course, screening does not cause prostate cancer, but in a practical sense, it does," he wrote. "More men must be told they have prostate cancer when screening PSA tests and follow-up biopsies are performed, and hence are at risk for anxiety and the harms related to further interventions."