The American College of Obstetricians and Gynecologists previously recommended mammograms every other year for women in their 40s, but the group - whose members often are the only doctors younger women routinely see - now believes annual testing will save more lives by catching cancers sooner. The association of gynecologists shifted away from its earlier wording suggesting that women “should have screening mammography’’ to a tone that simply advises doctors to offer it to patients.
That view comes in marked contrast to advice issued 20 months ago by the US Preventive Services Task Force, a government-appointed independent panel that created a furor when it stopped recommending routine mammograms for women in their 40s after determining the small benefits of screening at that age might not outweigh the harm from finding abnormalities that turn out to be benign.
Like the earlier task force, the gynecologists association says deciding to have a mammogram is ultimately up to each woman, saying women 40 and older should be offered the screening annually.
“Our thinking was that 40,000 women in their 40s are diagnosed every year with breast cancer and that 20 percent of these women who are diagnosed will ultimately die from the disease,’’ said Dr. Jennifer Griffin, an obstetrician-gynecologist at the University of Nebraska Medical Center and lead author of the new recommendations.
She insisted that her association was not trying to overturn the US Preventive Services Task Force recommendations, and Dr. Michael LeFevre, co-vice chairman of the task force, agreed. “I think they’re quite consistent with the task force recommendations,’’ he said.
LeFevre, who helped write the expert panel’s mammography recommendations, said the intent was to “empower women to make an informed decision for themselves and not just be told what to do.’’
That task force made clear that women should be screened starting at age 50, saying the benefits outweighed the risks.
The association of gynecologists, however, does not make a distinction between 40- and 50-year-olds, which some experts applauded. “The threshold of age 50 is totally arbitrary,’’ said Dr. Daniel Kopans, a Massachusetts General Hospital radiologist who has published numerous research papers on mammography. “The randomized clinical trials all start at age 40, not 50, and show a mortality benefit of at least 15 percent and as high as 30 percent.’’
All of the medical organizations issuing screening recommendations - including the American Cancer Society, which explicitly recommends yearly mammograms starting at 40 - rely on the same studies comparing breast cancer rates and deaths in women who have regular screening with those who do not.
“The evidence shows that most of the benefits of screening mammography are achieved by starting at age 50 and continuing to have screening every two years until age 75,’’ said LeFevre. That is because breast cancers become more common as women age, which means screening has the potential to save more lives for those in their 60s.
Without screening, 30 out of 1,000 US women are expected to die of breast cancer. But that drops to 23 out of 1,000 if women undergo screening every other year from age 50 to 75. Beginning screening every other year at 40 saves one additional life per 1,000 women screened, LeFevre said.
Increasing the frequency to every year would probably further reduce mortality, he added, but studies have never addressed that.
In recommending more frequent screening for 40-year-olds, the gynecologists’ group reasoned that since breast cancers grow faster in younger women, more frequent screening could catch more growths earlier.
But it is “a leap of faith’’ to assume that earlier detection via a mammogram can change the course of an aggressive cancer that is going to rapidly spread and kill a woman, said Dr. Lisa Schwartz of the Dartmouth Institute of Health Policy and Clinical Practice. It is not known, she said, how often mammograms detect slow-growing breast cancers that never would have become life-threatening yet still must be treated.
“The idea that it will be better for younger women to have more frequent screening,’’ said Schwartz, “is . . . not based on scientific evidence.’’
And early screening may carry significant downsides, including a 50 percent likelihood that a woman who starts screening at age 40 will test positive when she really has nothing to worry about, warranting follow-up screening or, less commonly, a biopsy.
Mindi Altman, 41, took her doctor’s advice to have annual scans when she turned 40. “Getting a mammogram every year just makes sense to me.’’
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