(Reuters Health) – Use of a blood test to detect prostate cancer fell after a U.S. government-back panel advised against using it, researchers found.
“I’m hoping that men are being allowed to make a choice and this decline reflects the fact that they prefer not to be screened,” said study author Dr. Otis Brawley, who is chief medical officer for the American Cancer Society in Atlanta.
However, some researchers fear the test, for a substance in the blood called prostate-specific antigen (PSA), is simply not being offered to men anymore, which could mean that more cancers will be diagnosed at advanced stages, leading to more deaths.
The U.S. Preventive Services Task Force (USPSTF) recommended against routine PSA screening in 2012.
Brawley told Reuters Health that 11 high-quality trials have examined the value of PSA screening, but only two found that the test saves lives.
“They all show that PSA screening is associated with potential harms,” he added. Those harms include treating slow-growing and possibly harmless cancers with prostate removal, which can leave lifelong complications.
“We’re talking about a large number of men who are diagnosed and needlessly treated,” Brawley said.
For the new study, he and his colleagues used a database of nearly 446,000 men to look at prostate cancers in the U.S. from 2005 through 2012.
Between 2005 and 2014, for every 100,000 men age 50 and older, the number of new cases of prostate cancer fell from 535 to 416, they report in the Journal of the American Medical Association.
This decline occurred among men with early-stage or localized prostate cancers, the researchers write.
Also, the percentage of men who reported PSA screening in the last year fell from 41 percent in 2008 to 31 percent in 2013.
A separate study in the same journal, led by Dr. Jesse Sammon of Brigham and Women’s Hospital in Boston, also found a decrease in PSA screening in the U.S. after the 2012 recommendation.
“Clearly this (USPSTF) recommendation has greatly reduced prostate cancer screening in the U.S., and that may or may not be a good thing and I don’t think it is,” said Dr. David Penson of Vanderbilt University Medical Center’s Department of Urologic Surgery in Nashville, Tennessee.
Penson, who wrote an editorial about the new research, said the across-the-board decrease in early-stage prostate cancers shows men aren’t being offered screening anymore, and it likely means there will be an increase in advanced cancers in coming years.
“That’s unfortunately what’s going to happen because of this recommendation,” Penson told Reuters Health.
Dr. Douglas Owens, a USPSTF member and professor at Stanford University in California, added in a statement to Reuters Health that more research is needed and that the Task Force is already starting the process of updating its recommendation.
“The Task Force understands that some men will continue to request screening and some doctors will continue to offer it,” Owens said. “Patients requesting screening should be provided with the opportunity to make informed choices to be screened that reflect their values about specific benefits and harms.”
Brawley said it could take up to 10 years to know if the USPSTF recommendation leads to more deaths from prostate cancer, but he doesn’t think that will be the case.
“What anyone can take away is that PSA screening went down and I believe it went down because of the USPSTF announcement,” he said.
SOURCE: bit.ly/1NBn5yN, bit.ly/1NBn3H1 and bit.ly/1NBn6me JAMA, online November 17, 2015.