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New mammography advice: Less is more

Wait till age 50? Some say task force is wrong.

WASHINGTON - Women in their 40s should not automatically be screened for breast cancer, and older women should have a mammogram every other year instead of annually, an influential federal task force has concluded, challenging a bedrock belief of cancer prevention.

In its first reevaluation of breast-cancer screening since 2002, the panel that sets government policy on prevention recommended the radical change, citing evidence that the potential harm to women having annual exams beginning at age 40 outweighs the benefits.

"We're not saying women shouldn't get screened. Screening does saves lives," said Diana Petitti, vice chairwoman of the U.S. Preventive Services Task Force, which released the recommendations yesterday in a paper being published in today'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 self-exams of their breasts and concludes that 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 testing, exams, and treatment were not always beneficial and, in fact, could harm patients. Mammograms produce false-positive results in about 10 percent of cases, causing anxiety and often leading to unnecessary follow-up tests and biopsies.

But the American Cancer Society, the American College of Radiology, and other expert groups condemned the change, saying the benefits of routine mammography had been clearly demonstrated and played 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 Kopans, a Harvard radiology professor. "It's crazy - unethical, really."

Oncologist Mary Daly, chair of the clinical genetics department at Fox Chase Cancer Center in Philadelphia, said the reevaluation was flawed by its reliance on data from outmoded technology, namely film mammography. Digital mammograms, the new standard, have reduced the false-positive rate in women under 50.

"I'm not pleased, because I don't want any more women to die of breast cancer than have to," she said. "I'm going to tell my patients to continue getting screened as they have been. I'm willing to sit down and go over the data if they want to."

Some experts questioned whether the new guidelines, coming in the midst of a national debate about the health-care system and costs, were designed more to control spending than to improve health. Beside prompting fewer doctors to recommend mammograms to their 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 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.

About 39 million women undergo mammograms each year in the United States, costing the health-care system more than $5 billion a year.

Susan Pisano, a spokeswoman for America's Health Insurance Plans, an industry group, said coverage was not likely to change because of the new guidelines. No changes are planned in Medicare coverage either, said Dori Salcido, spokeswoman for the Health and Human Services Department.

The task force's Petitti also denied that the panel was influenced by the health-care debate or cost issues.

The new guidelines were based on a comprehensive analysis of the medical literature that included an update of a Swedish trial involving some 70,000 women, 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 showed the added benefit of starting before age 50 was modest, the researchers found.

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 receive unneeded 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."

New Guidelines

The U.S. Preventive Services Task Force reviews research and recommends preventive care. Yesterday it updated breast-cancer screening guidelines.

Women who have mammography cut

the risk of dying from breast cancer by

15 percent. But since it's less common in women under 50, more must be screened to avert a death.

For women ages 40 to 49, mammograms incorrectly identify a potential cancer (a false positive) 99 times out of 1,000 mammograms, leading to unnecessary X-rays and biopsies.

For women 50 and

over, the false-positive rate is 83 per 1,000 mammograms.

Women should begin mammograms at age 50 - not age 40 - to reduce potential harms from false positives.

Screening should be done every other year because it achieves "most of the benefit ... with less harm."

Screening should continue until age 74.

SOURCE: U.S. Preventive

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