After combing through 50 years' worth of international studies weighing the risks and benefits of mammograms, Harvard Medical School researchers conclude that the decision about how often to have a mammogram should be based on your age and personal risk factors—not on some arbitrary, one-size-fits all guideline, according to a new study published in the April issue of the Journal of the American Medical Association.
The researchers estimate that having an annual mammogram reduces breast cancer deaths by about 19%. But that percentage changes depending on your age: For women in their 40s, mammography reduces breast cancer deaths by 15%; for women in their 60s, regular screenings slash the risk by 32%.
"Unfortunately, mammography is not a perfect screening test," says Nancy Keating, MD, co-author of the study and associate professor of health care policy at Harvard Medical School and associate professor of medicine at Brigham and Women's Hospital. "Some cancers will be missed, and a small number of people that might have died of breast cancer without screening will have their lives saved," she says.
If a mammogram can tell you whether or not you have breast cancer when it’s early enough to be treated successfully, why not just have one every year? Because after undergoing 10 years of regular mammograms, women in their 40s or 50s have a 61% cumulative risk of getting a false positive result, resulting in a lot of unnecessary stress, procedures, and expense.
The bottom line? Your age, family history, and whether (and when) you’ve given birth all change your risk of developing breast cancer. Your doctor should carefully consider all these factors when advising you about how often to have a mammogram.
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