Are prostate cancer screening tests really necessary?
By Michael Castleman for Live Right Live Well
No one knows for sure. While experts used to recommend prostate cancer screening using the blood test for prostate-specific antigen (PSA), no national medical organization currently encourages routine PSA screening. Instead, the American Cancer Society suggests that doctors “offer” the test annually and let men, starting at age 50, decide for themselves if they want it. The American Urological Association concurs, adding that African-American men or men with a family history of the disease should be offered the option at age 45.
Why the ambiguity? When Dartmouth researchers recently analyzed prostate cancer diagnoses and treatments after 1986 (the year the PSA test was introduced), they found that diagnoses and treatments rose by more than one million but deaths declined only slightly. And when National Cancer Institute researchers compared death rates from prostate cancer in 76,000 men, they found no significant difference between men who had had annual PSA tests and those who had not.
The truth is that “the cancer-predictive value of PSA testing is about 30 percent,” says Jason Wilbur, a clinical assistant professor of family medicine at the University of Iowa. “This means that fewer than one man in three with a high PSA actually has cancer.”
What’s more, when a high PSA does lead to a bona fide cancer diagnosis, doctors can’t tell if the tumor is potentially life threatening or indolent (meaning, very slow growing and not life threatening). “With PSA screening, you find a lot of indolent tumors that would never bother men at all,” says Dr. Walter Willett of the Harvard School of Public Health.
H. Gilbert Welch, professor of medicine and the lead author of the Dartmouth study, agrees. “For every man who avoids a prostate cancer death due to PSA screening, about 50 men have to be treated unnecessarily,” he says. So the question is, will you be the one man whose life is saved by PSA screening or one of the 50 men who end up undergoing unnecessary treatment? Not only does over-treatment waste health care dollars, but one-third of patients will develop serious problems as a result of treatment, including urinary and fecal incontinence as well as erectile dysfunction.
“What we need is a better screening test,” says Mark Harris, a professor at the University of New South Wales, Australia. Until then, talk to your doctor, discuss the pros and cons, then make the decision together.
To feature this article:
- please select all code below (Ctrl. + A)
- copy to your clipboard (Ctrl. + C) and
- paste (Ctrl. + V) into your website