Should We Stop Routine Prostate Cancer Testing?
A federal task force concludes that testing does more harm than good
Routine annual testing for prostate cancer could soon end for most men if the controversial recommendations of a federal advisory panel are accepted by internists and insurance carriers. The U.S. Preventive Services Task Force has concluded that doctors should stop using the prostate-specific antigen test to detect prostate cancer in men, issuing what it feels is a final verdict in a long-simmering health-care debate.
What is the PSA Test?
PSA is a protein produced by the cells of a man's prostate gland. Through a blood test, doctors measure the amount of PSA being produced by the prostate in nanograms per milliliter (ng/ml). In general, the higher a man's PSA level, the more likely it is that cancer is present, but no specific level guarantees that a man has prostate cancer or is cancer free. A level below 4.0 ng/ml has been considered normal, but recent studies have found prostate cancer in 15 percent of men with PSA levels below 4.0. PSA can also be elevated by any of a number of benign prostate conditions, like inflammation or enlargement. A man’s PSA level alone is not enough information to diagnose cancer, so a biopsy typically follows a test that indicates an abnormally high level. (Learn more about PSA testing from Next Avenue.)
The PSA test is one of two methods for early detection of prostate cancer that have been widely approved by the U.S. Food and Drug Administration. The other is the digital rectal exam, in which a doctor inserts a gloved finger into the rectum and feels the prostate gland through the rectal wall to check for bumps or abnormalities. Medicare and many insurance carriers cover an annual PSA test for all men 50 and older. Many doctors advise men at a higher risk because of a family history of prostate cancer to begin getting annual PSA tests at 40 or 45. One’s likelihood of developing prostate cancer increases with age, and African-American men are at higher risk than other groups, for reasons that remain unclear to researchers. African-Americans develop prostate cancer at a rate of about 230 cases per 100,000 men; whites develop prostate cancer at a rate of about 150 cases per 100,000. The mortality rate for African-American men with prostate cancer is also more than twice as high as that of white men.
Why the Test Could Be Dropped
The task force found that PSA testing saves about one life for every 1,000 men screened over a 10-year period, but that the risks far outweigh that benefit. About 100 to 120 men per thousand will test positive for an elevated level of PSA. Roughly 70 percent of those men do not have prostate cancer, but since there's no way to tell from PSA testing alone, most of those men will have a biopsy, which can have complications that include bleeding and infection. Even when cancer is found in the biopsy, most tumors are not immediately life-threatening. Still, 90 percent of men elect to undergo treatment when cancer is found in a biopsy, largely out of caution. This, the task force believes, is the real problem, because while a man's cancer may not be life-threatening, the treatment can be.
Treatment for prostate cancer usually involves surgery or radiation therapy. But according to the task force's analysis, out of every 1,000 men screened for PSA overall, 40 of them will eventually experience impotence or incontinence after electing to have surgery or radiation therapy following an elevated PSA result and biopsy; 2 out of every 1,000 men screened will have a heart attack or stroke; and one will develop a dangerous blood clot in the legs or lungs. Of men who elect to have surgery, 5 out of every 1,000 will die from complications within a month.
Prostate cancer is the second-deadliest cancer for men, but it also has very high survival rates, and, according to the National Cancer Institute, 70 percent of prostate cancer-related deaths occur after age 75. While the task force agrees that PSA testing has value for some older patients, and men in high-risk groups, it concluded that widespread testing of the general population can do more harm than good because a number of men who display an elevated level of PSA are likely to die sooner from prostate cancer treatments than they would from the cancer itself.
A Debate Continues
The task force's conclusions echo those of experts who have long criticized what they see as the overuse of PSA testing. “At best, there is a very small potential benefit from the PSA test and there are substantial known harms,” Dr. Virginia A. Moyer, a professor of pediatrics at Baylor College of Medicine in Houston and the chairwoman of the task force, wrote in USA Today. “Until we improve the test and treatment options, the U.S. Preventive Services Task Force recommends against screening for prostate cancer. Using a poor test does not make a bad disease any better.”
But supporters of the PSA test insist that abandoning it would be irresponsible. In a statement, the American Urological Association said it was "outraged" and "believes that the task force is doing men a great disservice by disparaging what is now the only widely available test for prostate cancer, a potentially devastating disease. ... When interpreted appropriately, the PSA test provides important information in the diagnosis ... risk assessment and monitoring of prostate cancer patients."
“PSA is really all there is out there for detecting prostate cancer early,” Dr. William Catalona of Northwestern University, who developed the test, said in a statement following the task force’s announcement. In an editorial published alongside the task force’s recommendation in the Annals of Internal Medicine, Catalona and a group of colleagues wrote that the panel relied on flawed evidence that understated the benefits of the test. Catalona's team urged health-care providers to make their own decisions about employing the tests, and wrote, “We believe that elimination of reimbursement for PSA testing would take us back to an era when prostate cancer was often discovered at advanced and incurable stages."
In a related editorial published in the Annals, however, Dr. Otis Brawley, chief medical and scientific officer of the American Cancer Society, wrote: “Many have a blind faith in early detection of cancer and subsequent aggressive medical intervention whenever cancer is found. There is little appreciation of the harms that screening and medical interventions can cause. ... We need to practice medicine on the basis of evidence.”
The Obama administration announced that Medicare will continue to cover the PSA blood test, and most insurers are expected to follow the agency's lead and continue to cover it as well. Both supporters and critics of the task force's recommendation advise men to consult their urologists about whether to have the test.