Harvard study has rekindled fiery medical debate and has left many women
confused about when to have mammograms. The researchers report that the vast majority of American
women who die from breast cancer are unscreened—and half of these fatalities
occur in women under 50.
this grim toll, the team urges that medical guidelines be changed to recommend
annual screening, starting at 40. This strategy, they conclude, is “the best
method for women to avoid death from breast cancer,” which claims the lives of
about 40,000 American women every year. Over a lifetime, the disease strikes one in eight women.
In a scientific
controversy that’s been dubbed the “a new salvo in [the] mammogram
experts have attacked the study as flawed, contending that it could leave women
in their 40s needlessly anxious, worried or bewildered.
criticism that’s been raised is that the study didn’t account for possible
differences between women who opted for screening and those who skipped the
test. For example, earlier research suggests that women who get mammograms tend
to have higher incomes, better education and overall health, and greater access
they may be more likely to consult a doctor as soon as they felt a lump, leading
to better outcomes, while their poorer, less educated sisters might be at
greater risk for fatal disease simply because they delayed getting medical
younger women for breast cancer has long been a contentious topic. Witness the
firestorm of controversy ignited when the US Preventive Services Task Force
(USPSTF) issued guidelines in 2009 that recommend
against routine screening for women in their 40s. The task force recommends
mammograms every two years for women ages 50 to 74.
“The USPSTF recommendations have created a lot
of confusion, because women in their 40s don’t know if it’s safe to skip
mammograms or not,” says Katherine Lee, MD, a
breast specialist at the Cleveland Clinic’s Breast Center.
What’s the Downside of Mammograms
for Younger Women?
guidelines are based on research showing that a much larger number of women in
their 40s must be screened to prevent one breast cancer death, compared to
women in their 50s or 60s.
younger women’s breast X-rays are harder to interpret, they are more likely to
suffer such harms as anxiety-inducing callbacks for additional imaging or even
biopsies when they don’t have cancer. And it’s also possible for mammograms to
miss some cancers.
force concluded that the harms outweigh the benefits for younger women, but
also stated that in the end, the decision whether to have mammograms should be
made by women in consultation with their doctors.
In the new
study, the Harvard Medical School team used “failure analysis” to analyze the
value of mammograms, using the cases of 7,301 women diagnosed with breast
cancer between 1990 and 1999 at Partners Healthcare hospitals in Boston. The women were tracked until 2007.
Of the 609
confirmed breast cancer deaths, 71 percent occurred in women who had not been
screened. The women’s median age at diagnosis was 49. For women who died from
any other cause during the study, the median age was 72.
premenopausal women, breast cancer tends to be biologically more aggressive, so
it has sometimes spread to other parts of the body by the time it’s diagnosed,”
Dr. Lee reports. The rapid progression of the disease in younger women may
explain why 50 percent of the breast cancer deaths analyzed by the Harvard team
occurred in women under 50.
in older women, the disease often progresses relatively slowly, adds Dr. Lee.
Dramatic Improvement in Breast
reported a dramatic improvement in breast cancer survival associated with
screening. In 1969, half of women diagnosed with the disease were dead 12.5
years later, compared with only 9.3 percent of women in the study, who were
diagnosed in the 1990s.
"This is a remarkable achievement, and the fact that 71 percent
of the women who died were women who were not participating in screening
clearly supports the importance of early detection," said co-author Daniel
Kopans, MD, of Harvard Medical School and Massachusetts General Hospital, in a