Jan. 11--The experts who sparked a passionate debate over the value of mammograms as a tool to screen for breast cancer are doubling down on the recommendations that earned them the ire of cancer groups, women's groups and a large contingent in Congress.
The final advice of a federally funded task force reiterates that after the risks and benefits are weighed, screening mammograms do the most good when women get them every other year between the ages of 50 and 74.
For the bulk of women -- those whose risk of developing breast cancer is average or below-average -- getting mammograms earlier or more often raises the likelihood of cancer scares and unnecessary follow-up treatments, they said.
For women over the age of 74, the federal panel said there's insufficient scientific evidence to make a recommendation.
The U.S. Preventive Services Task Force advised that some women in their 40s may elect to get mammograms after discussing the pros and cons with their doctors.
But the group cautioned that, for women still in their 40s, regular mammograms catch just a few preventable cancers while raising the risk of false-positives. The panel also made clear that for women between 40 and 74 who are at average risk of breast cancer, screening yearly is more likely to lead to overtreatment than it is to save lives.
The new recommendations are likely to affect women's decisions about getting mammograms in very real ways, as they guide insurers both public and private in decisions about what treatments to cover.
The strongest of its recommendations--in this case, biannual mammograms for women between 50 and 74--must, under the Affordable Care Act, be offered to insured women without co-payment.
But that requirement does not apply when the federal task force deems a treatment to have net benefits that are less than "moderate or substantial." As a result, mammograms for women still in their 40s need not be offered without co-payment by insurers.
After years of fervent activism, public health messaging and medical practice, the mammogram has become an annual ritual for many women over 40 in the United States. For some breast cancer advocacy groups, the benefits of that ritual have become an article of faith. Other experts have simply parsed the evidence differently. So the recommendation that such screening can start later and should take place less often has touched off confusion and controversy.
Anticipating the new guidelines, Congress last month passed a law requiring health insurance companies to adhere to a set of 2002 guidelines and pay for annual mammograms for women in their 40s. The American Cancer Society suggests women begin to get a yearly mammogram at age 45, switching to once every other year at age 55. And the American College of Obstetricians and Gynecologists, the physicians most likely to counsel women about breast cancer screening, recommends regular mammograms starting at age 40, as does the American College of Radiology.
"The most important message is that women have a choice," said Dr. Kenneth Lin, a family physician at Georgetown University Medical Center in Washington. "There's no wrong choice, especially if you're a woman in your 40s: you could start at 40, wait til you're 50 or start in between: those are certainly reasonable choices, given the evidence we have." Others clearly agreed to disagree with the Task Force's recommendations.
"I don't endorse these guidelines. I still strongly believe that all women, even average-risk women, should consider getting annual screening mammograms in their 40s," said Dr. Catherine Dang, associate professor of Cedars-Sinai's Breast Cancer Risk Reduction Program. Women might start to screen for breast cancer in their mid-40s, said Dang, but should then do so routinely, "because the risk for breast cancer definitely goes up as you get older."
With prospects for such resistance looming, the U.S. Preventive Service Task Force's findings, published Monday in the Annals of Internal Medicine, painstakingly outlined the scientific evidence at hand and weighed the fine balance between the potential benefits and harms of a range of screening regimens.
For every 1,000 women who are at average risk of developing breast cancer and who start getting mammograms at age 40, biennial breast cancer screening might avert a single death from breast cancer, the analysis concluded. But that benfit came with a downside: Compared to similar women in their 40s who were not screened, the average-risk women who were screened would get 576 more false-positive results from those screenings. And 58 would undergo biopsies that proved benign.
The most extreme risk, however, would be to women who get a false diagnosis and are treated for breast cancer unnecessarily. In a comparison of two groups of 1,000 women in their 40s--one that got biennial mammograms and the other that did not--the mammogram group would have two more women who were wrongly diagnosed with the disease and underwent treatment that was fraught with risk and provided no benefit.
There is, however, a key limitation of that analysis: It is based on women considered to be "at average risk" for developing breast cancer. For women whose risk of developing breast cancer is heightened by a family medical history, genes or other factors--experts say that mammograms starting at 40 might be more than justified: They might be advisable.
"This does not apply to high-risk patients at all," said Dr. Lusi Tumyan, breast imaging section chief at City of Hope in Los Angeles. For women with a previous history of breast cancer, a genetic predisposition to developing cancer or an immediate family history of cancer, more aggressive screening is called for, said Tumyan.
For those who don't fit into that category, she said, "my best advice is determine individualized risk and what a woman is comfortable with, recognizing there are going to be false positives and the risks of harm."
The Preventive Services Task Force says it has left that decision open to women and their physicians. They defended the task force's mandated role of undergirding medical practice with scientific evidence. Insurance coverage decisions, they added, "are the domain of payers, regulators and legislators."
"We cannot exaggerate our interpretation of the science to ensure coverage of a service," the panel members wrote in an editorial published Monday in the Annals of Internal Medicine. "This would lead to confusion regarding the state of science versus the politics of coverage."
An editorial penned by the Annals' editor-in-chief emphasized that point as well, chiding those who have charged the task force is restricting womens' access to mammography.
"Guidelines that mislead women about the net health benefits they can expect from mammography would disrespect our mothers, wives, daughters and sisters," wrote Dr. Christine Laine, who is also senior vice president of the American College of Physicians. "Let's douse the flames and clear the smoke so that we can see clearly what the evidence shows and where we need to focus efforts to fills gaps in our knowledge" about cancer screening, she added.
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