Adding to debate and doubt over the value of breast cancer screening, the American Cancer Society on Tuesday affirmed that mammograms save lives - but for the first time suggested women should start the X-rays later in life.
Until now, the venerable cancer organization's guidance has been simple: Yearly mammograms, starting at age 40, for as long as a woman is in good health.
The update says women at average breast cancer risk should have annual mammograms from age 45 to 54, then "transition" to every other year, but "have the opportunity to continue annually." Women aged 40 to 44 should have the "opportunity" for annual screening, but should not automatically do it because of "less certainty about the balance of benefits and harms" in that age group. Women should stop mammograms when they have a life expectancy of less than a decade.
The senior author of the new advice, Richard Wender, a Thomas Jefferson University family physician, said in an interview that the new guidance is "more personalized and tailored. I think it will create more clarity."
Other experts think the opposite.
"I just felt like it's very vague and confusing," said Jean Sachs, chief executive officer of Living Beyond Breast Cancer in Bala Cynwyd.
"I think the guidelines are a bit complicated and confusing for the general population and clinicians," said Houston cancer prevention specialist Therese Bevers, who coauthored the breast cancer screening guidelines of the Fort Washington-based National Comprehensive Cancer Network.
The network and most other groups - including the American College of Obstetricians and Gynecologists and Ardmore-based breastcancer.org - continue to recommend mammograms for women beginning at age 40.
But the issue of when to start screening has divided the medical community since the late 1980s.
Compared with older women, women in their forties have a relatively low risk of breast cancer, so many more need to be screened to save one life. Yet because their breast tissue tends to be denser, they are more likely to have false alarms - which means anxiety, additional imaging, and possibly unnecessary biopsies, with the attendant risks of minor surgery.
In recent years, the debate has become even thornier.
Many states, including Pennsylvania, have passed laws requiring that women be informed if they have dense breasts so they can consider ultrasound or MRI imaging. Cancer in younger women is usually more aggressive, yet it is not clear that early detection makes such cancers more curable. Conversely, some tiny tumors revealed by mammograms would never cause problems if left alone, yet because there is no way to be sure, women are almost always treated - overtreated, critics say.
Another recent development: three-dimensional mammography, or tomosynthesis, is becoming widely available and has been shown to find more cancers while reducing false alarms.
Tomosynthesis is "tipping the benefit-to-risk ratio greatly," said radiologist Emily Conant, chief of breast imaging at the University of Pennsylvania. "Let's not stop looking [for breast cancer]. Let's just look with better technology."
Another bit of context for the ACS guidelines came in 2009. The U.S. Preventive Services Task Force, an independent expert group, recommended that routine mammograms begin at age 50 rather than 40. That set off controversy, and resulted in an estimated 10 percent drop in mammography rates among fortysomethings three years later. Because USPSTF guidance is used by many insurers and government programs to determine coverage, it also led Congress to intervene to keep mammogram coverage intact.
In April, the task force issued an updated proposal reiterating the recommendation to start screening at 50.
Adopting a more conservative starting age brings the ACS "closer to the USPSTF guidelines," noted an editorial accompanying the ACS guidelines, published Tuesday in the Journal of the American Medical Association.
Christina Meehan, 34, a marketer from Ardmore, does not think such conservatism is prudent, based on her own unusual experience. Two years ago, she went to her doctor with breast swelling and redness. A mammogram and tests led to a diagnosis of inflammatory breast cancer, a rare, aggressive form.
"A lot of people look to the ACS as the organization that sets the standards," Meehan said. "If a woman who is 35 or 40 is having an issue with her breast, but she thinks 'Oh, the ACS says don't start mammograms until 45,' it may deter her from getting it checked out."
The question of how beneficial mammography is to women in their forties - and whether that outweighs the risks of false alarms and overtreatment - has no simple answer.
Most analyses of clinical trials estimate mammography reduces the risk of dying of breast cancer by 15 percent for women in their forties, compared with 30 percent for women in their fifties. By reviewing more recent but less rigorous studies, the ACS guidelines committee estimated the "mortality benefit" for women in their forties could be as high as 40 percent.
"It should put to rest any question about whether mammography reduces mortality," said Wender, chief cancer control officer at ACS.
But the ACS committee - which conducted an exhaustive medical literature review and solicited critiques from breast cancer advocates and experts - also concluded that lumping together all women in their forties obscures important age-related differences in breast cancer benefits and harms. It advised screening starting at age 45 based on the finding that women in their late forties are more similar to women in their fifties than to those in their early forties.
In another departure from the past, the ACS advised clinicians to stop doing routine clinical breast exams - feeling the breast for abnormalities - because it hasn't been rigorously studied and seems to increase false alarms.
The ACS stance on clinical exams is even more negative than the USPSTF, which said there isn't enough data to advise for or against the practice.
"I'm a bit surprised" by the ACS's rejection of clinical exams, Bevers said. "They went from recommending it to the other extreme. There is no new data on which to base such a dramatic change."
The ACS guidance urges doctors to discuss the pros and cons of screening with women. It suggests that, given the time constraints of the typical visit to the doctor, the discussion should take the place of clinical breast exams.