Image of Karla Kerlikowske, M.D.; Image credit: UC San Francisco
Karla Kerlikowske, M.D.; Credit: UC San Francisco

The very small number of breast cancer deaths averted by annual mammography in women aged 75 years and older may not balance out the potential harms of overdiagnosis, a new study has found.

Currently, recommendations for mammography for older women differ due to the lack of older women in the clinical trials used to set guidelines, the authors noted. The U.S. Preventive Services Task Force, for example, recommends mammogram screening every other year until 74 years of age, while the American Cancer Society advises mammograms for women beyond that age if they have a life expectancy of 10 or more years.

With the goal of filling in the missing information, researchers for the National Cancer Institute and the National Institute of Health compared breast cancer death, survival and cost with annual or biennial mammography screening from age 65 years to ages 75, 80, 85 and 90 across comorbidity levels. They found that annual mammography did not provide more quality of life or cost benefits than harm. In contrast, biennial screening to age 80 years did provide more benefit than harm, but the absolute number of deaths averted is small, especially for women with other underlying health conditions, the study revealed.

“Women considering screening beyond age 75 years should weigh the potential harms of overdiagnosis versus the potential benefit of averting death from breast cancer,” the authors concluded.

Full findings were published in the Annals of Internal Medicine.