When the blood test for prostate cancer was introduced 26 years ago, it was seen as a way to save lives.
But research since then has questioned this conclusion and a large new study, published last week, adds more doubt to the issue. The long-term study of 76,000 men ages 55 to 74 found that routine prostate-specific antigen (PSA) testing did not prevent deaths from prostate cancer.
However, some prostate cancer experts immediately criticized the study, and even one of the co-authors acknowledged that while routine mass screening is not the way to go, "we don't need to throw out PSA testing altogether," Gerald L. Andriole Jr. of Barnes-Jewish Hospital in St. Louis told the Washington Post.
Andriole explained that the PSA test doesn't indicate whether a prostate tumor is a slow-growing, nonfatal kind, or the more lethal kind. As a result, many men undergo unnecessary surgery, radiation and drug therapy that can leave them incontinent or impotent.
However, William Catalona, M.D., director of the clinical prostate cancer program at Northwestern University and considered the father of the original PSA test, called the study "flawed," telling the Post that "it doesn't really address the question of whether PSA screening saves lives."
The study, funded by the National Cancer Institute, followed the men at 10 sites nationwide for 13 years. Half received annual PSA tests for six years along with digital rectal exams, which also can help detect prostate tumors; the other half continued under the care of their regular doctors.
As it turns out, half of those in the "regular doctor care" group received PSA testing because that's been the standard of care since the 1990s. And that's the problem: For this study to have been an ideal test of whether screening really saves lives, none of the men in this group should have been tested.
Instead, researchers found after 13 years that more men in the screening group were diagnosed with cancer, but there was no difference in the number of deaths between the two groups. The researchers then concluded that routine screening doesn't save lives.
But other experts disagreed. Scott Eggemer, M.D., a urologic cancer specialist with the University of Chicago Medical Center, said the research "ends up being a study of intensive screening versus fairly intensive screening. You can't really make sense of it," he told Reuters.
So where does this all leave older men wondering about having a PSA test or not?
Study co-author Phillip Prorok, of the National Cancer Institute, says that men need to be aware that there's a possibility that PSA testing has little or no benefit, and there may be some harm.
The best thing to do is talk it over with your doctor. For some men, doing a baseline PSA test to be followed up every couple years is enough. For those with a family history of the disease, they may benefit from regular screening.
Photo credit: seniorwellnessspecialists.blogspot.com