Federal task force makes radical change in breast cancer screening guidelines
By Rob Stein
Washington Post Staff Writer
Monday, November 16, 2009; 4:58 PM
Women in their 40s should stop routinely getting annual mammograms, and older women should cut back to one scheduled exam every other year, an influential federal task force has concluded, challenging the use of one of the most common medical tests.
In its first reevaluation of breast cancer screening since 2002, the federal panel that sets government policy on prevention recommended the radical change, citing evidence that the potential harms of all women getting annual exams beginning at age 40 outweigh the benefits.
"We’re not saying women shouldn’t get screened. Screening does save lives," said Diana B. Petitti, vice chairman of the U.S. Preventive Services Task Force, which released the recommendations Monday in a paper being published in Tuesday’s Annals of Internal Medicine. "But we are recommending against routine screening. There are important and serious negatives or harms that need to be considered carefully."
The task force’s new guidelines — which also recommend against teaching women to do regular formal self-exams of their breasts and concludes there is insufficient evidence to continue routine mammograms beyond age 74 — immediately triggered intense debate.
Several patient advocacy groups and many breast cancer experts praised the shift, saying it represented a growing recognition that more tests, exams and treatments are not always beneficial and, in fact, can harm patients. Mammograms produce false-positive results in about 10 percent of cases, causing anxiety and often prompting women to undergo unnecessary follow-up tests, sometimes-disfiguring biopsies, and unneeded treatment, including surgery, radiation and chemotherapy.
But the American Cancer Society, the American College of Radiology and other experts condemned the change, saying the benefits of routine mammography have been clearly demonstrated and play a key role in reducing the number of mastectomies and the death toll from one of the most common cancers.
"Tens of thousands of lives are being saved by mammography screening, and these idiots want to do away with it," said Daniel B. Kopans, a professor of radiology at Harvard Medical School. "It’s crazy — unethical, really."
Some questioned whether the new guidelines, coming in the midst of an intense debate about the health-care system and costs, were designed more to control spending than to improve health. In addition to prompting fewer doctors to recommend mammograms to patients, they worried, the move would prompt Medicare and private insurers to deny coverage of many mammograms.
The new recommendations took on added significance because under health-care reform legislation pending in Congress, the conclusions of the 16-member task force would set standards for what preventive health-care services insurance plans would be required to cover at little or no cost.
About 39 million women undergo mammograms each year in the United States, costing the health-care system more than $5 billion a year.
Petitti denied that the panel was influenced by the health-care reform debate or cost issues.
A spectrum of women’s health advocates, breast cancer experts and public health researchers praised the new guidelines.
"It’s about time," said Fran Visco, president of the National Breast Cancer Coalition, a Washington-based patient advocacy group. "Women deserve the truth — and the truth is the evidence says this is not always helpful and can be harmful."
Susan Love, a well-known breast cancer expert at the University of California at Los Angeles, agreed. "I think that we’ve oversold early detection. We got carried away with a slogan," Love said. "We’re not saying don’t do it. Some women should get routine screening. But not all. We think in our society that more is always better. What we’re saying is, ‘It’s not.’ "
While the American Cancer Society said it has no plans to changes its guidelines, the National Cancer Institute said it would reevaluate its recommendations in light of the task force’s conclusions.
The change is the latest development in a long controversy about mammography. The American Cancer Society and other groups have long recommended that women regularly undergo the tests every one or two years beginning at age 40 to catch tumors.
More than 182,000 women are diagnosed with breast cancer each year in the United States, and the disease kills more than 40,000, making it the second most common cancer after skin cancer and the second leading cause of death from cancer among women after lung cancer.
Deaths from the disease have dropped significantly in the United States and elsewhere since routine mammograms became common. But there has been intense debate about how much of that reduction was because of screening and how much was because of other factors, such as improved treatment.
Many experts have begun to raise questions about a number of routine screening methods, including the PSA blood test for prostate cancer, as well as mammography, because the screening often triggers false alarms and catches pre-cancerous growths and tiny tumors that would never become life-threatening but nonetheless prompt treatment.
The new guidelines were based on a comprehensive analysis of the medical literature, including an update of a Swedish study involving some 70,000 women, new results from a British trial involving more than 160,000 women and data from more than 600,000 women from the U.S. Breast Cancer Surveillance Consortium.
In addition, the task force commissioned an unusual study funded by the National Cancer Institute that involved six independent teams of researchers conducting separate mathematical modeling studies of the risks and benefits of 20 different screening strategies.
While annual mammography for all women beginning at age 40 reduced the death rate from breast cancer by at least 15 percent, the modeling studies indicated that the added benefit of starting before age 50 was modest, the researchers concluded.
For every 1,000 women screened beginning at age 40, the modeling suggested that just 0.7 deaths from breast cancer would be prevented, while 480 women would get a false-positive result and 33 more would undergo unnecessary biopsies.
"What isn’t in the model but is an issue is how many extra imaging tests are done to follow up on things that turn out to be falsely positive, and the harm of the anxiety that goes along with that," Petitti said. "Then there’s the whole other line of problems that come into play, which is where there are some breast cancers detected that grow very slowly and would never have killed you."
Cutting back to biannual screening of women age 50 and older would maintain 81 percent of the benefits of screening annually while reducing by half the number of false-positives, the computer modeling study estimated.
Petitti stressed that the task force is not recommending against mammography but hopes the new guidelines will lead more women to make their decisions individually. Those at high risk because of a family history of breast cancer, for example, or those who are simply more worried about breast cancer might still opt to get annual screenings, she said.
While the task force recommended against doctors teaching women how to perform regular breast self-exams and concluded that there was insufficient evidence to determine whether doctors’ examinations of a woman’s breasts are beneficial, several experts stressed that women should seek medical attention if they come across any unusual lumps spontaneously.
Others worried that the conflicting advice will prompt women to delay the exams or avoid them completely.
"People will end up not getting mammograms — they’ll just kiss them off," said Judith Luce, who treats breast cancer patients at San Francisco General Hospital. "I’m concerned the sense of urgency about getting them done will fade."