By Rob Stein
Washington Post Staff Writer
Tuesday, August 5, 2008
The blood test that millions of men undergo each year to check for prostate cancer leads to so much unnecessary anxiety, surgery and complications that doctors should stop testing elderly men, and it remains unclear whether the screening is worthwhile for younger men, a federal task force concluded yesterday.
In the first update of its recommendations for prostate cancer screening in five years, the panel that sets government policy on preventive medicine said that the evidence that the test reduces the cancer's death toll is too uncertain to endorse routine use for men at any age, and that the potential harm clearly outweighs any benefits for men age 75 and older.
"The benefit of screening at this time is uncertain, and if there is a benefit, it's likely to be small," said Ned Calonge, who chairs the 16-member U.S. Preventive Services Task Force. It published the new guidelines today in the Annals of Internal Medicine. "And on the other side, the risks are large and dramatic."
The task force and other groups concluded previously that it was unclear whether the benefits of the prostate-specific antigen, or PSA, test outweigh the risks. The new review of the scientific literature found no evidence to alter that assessment for younger men. It did find enough new data to recommend for the first time against screening for older men.
"We felt with sufficient certainty that your risk of being harmed exceeded your potential benefits starting at age 75," Calonge said.
The recommendations come at a time when doctors are increasingly questioning whether many tests, drugs and procedures are being overused, unnecessarily driving up health-care costs and exposing patients to the risks of unneeded treatment.
"There is this idea that more is always better, and if a test is available we should use it," said Howard A. Brody, a professor of family medicine at the University of Texas Medical Branch at Galveston. "A lot of times, we're doing more harm than good."
The guidelines address perhaps the most important and contentious issue in men's health, and were praised by officials at several leading medical groups, including the National Cancer Institute and the American Cancer Society. But they drew strong criticism from others who are convinced that routine screening is necessary.
"I think they're really missing the boat," said William J. Catalona, a professor of urology at Northwestern University. "It's a disservice to patients. A lot of men die from prostate cancer, and there's just an overwhelming amount of evidence that screening saves lives."
Each year, prostate cancer is diagnosed in more than 218,000 U.S. men. About 28,000 die of it, making it the most common cancer and second-leading cancer killer among men.
The PSA test, which measures a protein in the blood produced by prostate tissue, has significantly increased the number of prostate cancer cases being diagnosed at very early stages. But it remains unclear whether that translates into a reduction in the death rate from the disease. Prostate cancer often grows so slowly that many men die from something else without ever knowing they had it.
Because it is not clear precisely what PSA level signals the presence of cancer, many men experience stressful false alarms that lead to unnecessary surgical biopsies to make a definitive diagnosis, which can be painful and in rare cases can cause serious complications.
Even when the test picks up a real cancer, doctors are uncertain what, if anything, men should do about it. Many men simply are monitored closely to see if the tumor shows signs of growing or spreading. Others undergo surgery, radiation and hormone treatments, which often leave them incontinent, impotent and experiencing other complications.
"People say, 'What's the harm in screening?' In fact, there are several ways in which screening can actually be harmful," said Howard L. Parnes of the National Cancer Institute.
Since the task force issued its previous recommendations in 2002, at least eight new studies have been published. Among them was a large Swedish review that found that men age 65 and older who were treated for prostate cancer were no more likely to survive than those who were not.
"If therapy isn't providing meaningful benefit, then how could screening provide benefit?" Calonge said. "And we know that the therapy produces significant harms."
Men younger than 75 should be carefully counseled about the potential risks associated with the test and the lack of evidence about any benefit before getting it, the panel said.
Men at high risk for prostate cancer, such as African Americans and those with a family history of the disease, are the most likely to benefit from PSA screening. But the panel concluded that the evidence remains inconclusive for those men as well.
Several other experts said that the new recommendations strike a careful balance, and that they hope they might discourage large-scale screenings where the risks and benefits are not carefully laid out.
"I think they are right on target," Parnes said.
Others were highly critical, noting that prostate cancer death rates have plummeted in many countries after they instituted widespread PSA screening.
"We have seen a dramatic drop in mortality," said J. Brantley Thrasher, chairman of the urology department at the University of Kansas and a spokesman for the American Urological Association. "They're not paying attention to that."
Others objected to setting an age cutoff, saying men should be evaluated individually.
"Men are living a lot longer and healthier these days. I play golf with 84-year-old guys who beat me all the time," said E. David Crawford, a professor of surgery and radiation at the University of Colorado at Denver. "You have to individualize treatment. If a 75-year-old man is found to have high-grade prostate cancer, it's going to kill him, and we can intervene and do something for him."
Two large studies are underway -- one in the United States and one in Europe -- to answer the question of whether screening reduces mortality.
"If it turns out that PSA screening and aggressive treatment saves lives, maybe all the harm that it has caused is worth it," said Otis W. Brawley, chief medical officer at the American Cancer Society. "If PSA screening does not save lives, then it's clearly not worth it. We just don't know yet."