Prostate Cancer:
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Pros & Cons Some say it can do more harm than good. By Christopher Conte Since the “PSA” blood test became available 10 years ago, millions of American men have been screened regularly for prostate cancer. But as the U.S. Postal Service found in 1999 after issuing a stamp that encouraged prostate checkups routine tests are a sore –and divisive–subject within the medical profession. The Postal Service’s endorsement of particular health policies and behavior has been misguided and counterproductive, “fumed Steven Woloshin, M.D., and Lisa M. Schwartz, M.D., in the New England Journal of Medicine. While the Postal Service believed it was championing an accepted health strategy, the two doctors, of the Veterans Affairs Medical ad Regional Office Center in Vermont, said the agency’s campaign spread “serious misconceptions about the benefit of early detection in general and an unwarranted optimism about screening for prostate cancer in particular.” Doctors who oppose screening healthy men say it hasn’t yet proven beneficial—and may do more harm than good by leading to unnecessary and expensive follow-up tests and treatments that can cause incontinence or impotence. But screening is stoutly defended by other doctors. Like William Catalona, M.D., professor of urology at Washington University School of Medicine in St. Louis.” No cure for advanced prostate cancer is available or on the horizon,” he told the AARP Bulletin. “The only practical strategy is to screen it, detect it early and treat it.” Which group is right? No-body knows for sure. “The issue has been murky,” says Durado Brooks, M.D. director of the prostate and colorectal cancer programs at the American Cancer Society. “It is hard to get the sort of clear, scientific answer we’d like to see.” Definitive answers may have to await the result, several years hence, of a National Cancer Institute study that is tracking 74,000 men to see if those screened routinely for prostate cancer fare better than those who aren’t. In the meantime, men must weave their way through a maze of uncertainty and conflicting expert opinion to decide about testing. The stakes are high. Last year over 179,000 American men were diagnosed with prostate cancer, the second-leading cause of cancer death after lung cancer. Nobody disputes that a reliable early-detection system is needed According to the American Cancer Society, three out of four men whose cancer is found while still confined to the prostate survive for a least 10 years. Just 15 percent will live that long if the cancer has spread to distant parts of the body. Agreement breaks down, though over the reliability of available tests and whether prostate cancer detected early actually requires treatment. The disease often develops slowly—so slowly, in fact, that many men who have it are not aware of it and die of their causes. The disease primarily afflicts older men—only 8.5 percent of prostate cancer deaths occur in men under age 65, according to the National Cancer Institute, while almost two-thirds of the deaths occur in men over 75. One routine test for prostate cancer is the digital rectal exam. But it’s the PSA blood test that is so controversial. It measures prostate-specific antigens (PSAs) produced by the prostate, a small gland near the bladder that is involved in semen production. PSA readings below 4 nanograms per milliliter (ng/ml) of blood are considered normal, while higher readings cold indicate cancer. But anxiety-inducing false alarms are common, since elevated scores occur frequently in men with no cancer but with inflamed or enlarged prostates—a common condition in older men. Today doctors usually track changes in PSA levels over time for a more accurate picture than a one-time score provides. An increase of say, 0.75 ng/ml over a year could signal trouble even if a score is still quite low. Publicity about PSA tests, along with testimonials from celebrities like Bob Dole and Arnold Palmer who have been tested and successfully treated, have led more men to seek screening than ever before. And more men are being diagnosed and receiving treatment, including surgical prostate removal. Taking fast action may bring peace of mind, but many doctors advocate “watchful waiting” to see if the cancer develops and if treatment is needed and with good reason. Studies have found that as many as 85 percent of men experience at least some degree of impotence after prostate surgery, and as many as 27 percent may become incontinent. Similar complications may arise from other treatments such as radiation and cryosurgery, which freezes cancerous tissue to kill it. Given such uncertainties, some organizations like the National Cancer Institute and the U.S. Preventive Services Task Force do not support mass screening. Other groups such as the American Cancer Society and the American Urological Association, Association, have revised their guidelines: They still suggest periodic testing for healthy men over 50 or for younger men at risk for prostate cancer but now advise doctors to inform men about the pluses and minuses of screening and treatment; they leave the decision on testing up to the individual. {See box below on how you decide}.
Some men may agree to the PSA test because it’s simple and, at about $80, fairly cheap (and covered by Medicare and most private health insurers). But they often don’t know the possible consequences. “Once you agree to be screened, you’re on a slippery sloop,” argues Richard Roberts, M.D., professor of family medicine at the University of Wisconsin Medical School. If a PSA test suggests cancer most men want to know for sure. They agree, perhaps, to an ultrasound scan and a biopsy to check for malignant cells. If cancer is present, most men want immediate treatment—even if the disease poses little risk to them. We have bought into a cultural myth that doing more is doing better,” Roberts says. “But a lot of time, doing more is just doing more.” When the issues are fully explained to them, Roberts says, many men decide against the PSA test. “About three-quarters of the men I see look at the data and say, ‘leave me alone, don’t do any tests.’” Many patients who opted for surgery or radiation, he adds, say they would have refused treatment had they known more in advance. “A lot of guys who show up in the office saying they were feeling fine before, but now they feel miserable,” he reports. Catalona of Washington University thinks such regrets are misguided. He says most of the prostate cancers he has discovered through PSA scores and other tests are not the slow-growing variety. “The vast majority of cancers that are being detected are serious ones that would cause problems.” Catalona may be right, but Barry Karmer, M.D. of the National Institutes of Health says not enough is known about the early-stage cancers to be sure which types pose a real threat. If a cancer is surgically removed, he says, “you can’t predict what it would have done if you had left it alone.” In the face of such uncertainty, researchers are looking for other, more accurate ways to diagnose prostate cancer and improve the PSA test. Treatments are being refined too. New surgical and radiation techniques are lowering risks of impotence or incontinence. Still, at the moment, no risk-free answers exist to the dilemmas healthy men face in deciding whether to undergo screening. “There is no right or wrong, ”says Bruce Bagley, M.D., an Albany, N.Y., physician and former president of the Academy of Family Physicians. “Patients have to weigh the findings and their own attitudes about health and disease.”
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