For years, women have been taught to perform regular breast self-exams and those 40 and older told to undergo annual mammograms to detect breast cancer, a disease that kills about 40,000 people in the U.S. every year. Now, new guidelines released by an influential government-funded authority on screening offer this message: never mind.

The new U.S. Preventive Services Task Force guidelines, published Monday in the Annals of Internal Medicine, state that routine mammograms aren't necessary for women of average cancer risk in their 40s, and that women between 50 and 74 years old don't need to undergo mammograms more often than every other year. They also recommend that physicians abstain from teaching women how to examine their breasts for signs of cancer because of a lack of evidence that it is of any benefit.

The guidelines were based on a routine review of research published since the last set of recommendations and a new analysis of data. The guidelines were formed by weighing benefits of screening compared with the harms of false positives, such as anxiety and unnecessary additional tests and biopsies, which are expensive and time-consuming, according to Diana Petitti, vice-chairman of the task force.

The task-force recommendations only apply to women without a family risk of breast cancer and who don't have genetic mutations known to be associated with breast cancer, such as the presence of BRCA1 or BRCA2 genes.

By scrubbing the previous recommendation of annual mammograms for women 40 and older, the new guidelines are likely to be controversial and confusing. They also raise concerns that health insurers will curtail coverage and reimbursements for screenings that fall outside the guidelines, according to doctors and groups including the American Cancer Society.

Phil Evans, a professor of radiology at the University of Texas Southwestern Medical Center and president of the Society for Breast Imaging, says he was "shocked" by the changes. "There's a ton of scientific data in this country and others on screening that shows a significant benefit for women between 40 and 49 to be screened," he says.

The National Comprehensive Cancer Network, the American Cancer Society and the American Medical Association recommend annual mammograms for women starting at age 40, while the American College of Physicians recommends women in their 40s decide for themselves whether to seek annual exams.

The task force, which receives funding from the federal Agency for Healthcare Research and Quality but is independent from the government, last issued guidelines for breast cancer in 2002. "The task force isn't saying there isn't a benefit" to screening women in their 40s, but "we're saying the benefit is small," Dr. Petitti said. "The change really is a change between do it routinely and don't do it routinely." Women 40 and older who are free of any symptoms should talk with their doctors and decide with them whether to put off screening for a few years, she said.

Dr. Petitti's advice is less nuanced about the issue of breast self-examinations. "Women should know it doesn't work," she said. Two large studies published since the last guidelines, involving 200,000 women in China and more than 100,000 in Russia, showed no benefits from breast self-examinations, she said.

There is agreement among scientists that mammography saves lives but that it also gives rise to numerous false positives. It reduces cancer death by about 15% in women ages 39 to 59, according to the task force's review of published data.

There are fewer cases of cancer in younger women, which means there are fewer absolute benefits when weighed against risks for women in their 40s. For each case of cancer death prevented among younger women, 1,900 women must be screened, according to the task force's review of published data. That ratio drops to 1 for 1,300 for women 50 to 59 years old, and 1 for 377 for women 60 to 69 years old, according to the task force.

The task force's interpretation of the data overstates the downsides of mammography for women in their 40s and doesn't take into account the fact that saving a younger woman leads to more "life years saved" than for older women, Dr. Evans says.

About $3.3 billion was spent on mammograms in the last 12 months, according to the American College of Radiology.

USPSTF Breast Cancer Screening Guidelines: Then and Now


2002: Recommended every 1 to 2 years for all women older than 40

2009: Recommends against routine screening for women 40 to 49; recommends mammograms every 2 years for women 50 to 74; insufficient evidence to conclude benefit or harm of mammograms for women 75 and older

Breast Self-Examination

2002: Insufficient evidence to conclude benefit or harm

2009: Recommends against teaching BSE

Digital and MRI Mammography

2002: Not addressed in guidelines

2009: Insufficient evidence to conclude benefit or harm

Source: U.S. Preventive Services Task Force guidelines published in 2002 and 2009

Whether the new guidelines lead to changes in insurance reimbursement is likely to be a big concern among health providers and patients.

The Centers for Medicare and Medicaid Services, which administers government health benefits for the elderly and the poor, says the new guidelines wouldn't change how it covers mammograms for Medicare patients. But that may not be the case for private insurance. The task force guidelines tend to influence public and private insurers' coverage decisions, though they aren't the only factor, according to John Ayanian, a professor of medicine and health-care policy at Harvard Medical School who published a paper last year on the impact of cost-sharing on mammogram usage rates in the New England Journal of Medicine.

Susan Pisano, spokeswoman for America's Health Insurance Plan, an industry trade group, says she anticipates mammogram coverage will continue even for those who fall outside the new guidelines' target age range. What may change, she says, are insurers' aggressive outreach efforts to get women to get their screening, such as the reminder postcards they used to receive about getting their annual mammogram.

Eric Winer, chief scientific adviser of Susan G. Komen for the Cure, a breast-cancer advocacy foundation, and director of the Breast Oncology Center at Dana-Farber Cancer Institute in Boston, says that "at a minimum, what we can say is that women and their doctors have a right to make a decision about whether they should be screened. If they don't have financial coverage, then they don't have that right."

Write to Shirley S. Wang at