The analysis, published recently in Annals of Internal Medicine, stirred up controversy, with some experts in cancer screening and statistics claiming it used a “completely unverifiable” methodology that they had “never seen before.” Others supported its “intriguing and innovative approach.” The opposing sides did find common ground on one subject matter, however. “I imagine it’s going to generate some buzz,” said biostatistician Ted Karrison of the University of Chicago,
as reported by Business Insider.
The controversy around prostate cancer screening mirrors that of breast cancer screening: Routine testing can be life-saving, but it can also lead to unneeded and potentially harmful treatment in people who don’t need it.
One of the earlier trials, conducted in Europe, determined that screening reduced deaths from prostate cancer by 21 percent. At the same time, however, it also led to many harmful and even unnecessary interventions. Another trial, based in the United States, didn’t find any difference in death rates between men who had been randomly screened and those that hadn’t.
The new analysis included some of the investigators in the original studies, as well as various other scientists. Together, they reanalyzed the data from the two trials using different mathematical models. The team concluded that, when comparing men who had undergone screening to those who hadn’t, screening tests were found to have reduced prostate cancer deaths by 25 to 32 percent.
“By the time the U.S. trial started, a lot of the population was already being screened for prostate cancer,” Ruth Etzioni of the Fred Hutchinson Cancer Research Center, the senior author of the new paper, told The New York Times. And about three-quarters of the men in the group not assigned to screening were still getting tested as part of routine medical care, The New York Times reports.
According to Andrew J. Vickers, an attending research methodologist at Memorial Sloan Kettering Cancer Center, it’s clear that PSA screening can curb prostate cancer death rates. “The debate shouldn’t be to screen or not to screen, but how can we change screening so it does not cause harm,” Dr. Vickers told The New York Times.
“It’s not a take-it-or-leave-it,” Dr. Vickers said. “A PSA test cannot really harm you or save your life. What can harm you is if the test leads you to get treatment you don’t need, and what can save your life is the PSA test that finds the cancer that could kill you.”
Still, critics warn that the dangers of PSA screening outweigh any good. Harvard Health Publications reports that PSA tests commonly alert doctors to the presence of cancer, but without the ability to determine if the cancers detected would have ever caused symptoms or harm during a man’s life. “One study estimated over-detection to rise with age, from 27 percent at age 55 to 56 percent by age 75,” according to Harvard’s report. Most men choose what they view the safest route, opting for treatment, which frequently leads to side effects like incontinence and impotence.
Nevertheless, for men who have been weighing the pros and cons of PSA screening, the new analysis strengthens the evidence that testing can reduce deaths from this cancer.
Experts urge that men who have a family history of prostate cancer or any symptoms of the disease should be screened. Older African-American men should also be screened, as they are at higher risk for prostate cancer. Men aged 55 to 69 who do not fall into these categories have, at the very least, more information to help them decide.
Here’s how to lower your risk of prostate cancer.