Annual mammography after age 75 may not be beneficial; every other year has better cost/benefit ratio

A modeling study found that the very small number of deaths averted from breast cancer may be offset by costs and potential harms of overdiagnosis with mammography done annually after age 75 years.

A modeling study concluded that screening mammography every year after age 75 years did not provide more benefit than harm in terms of a woman's quality of life and cost of care. While mammograms every other year from ages 75 to 80 years provided more benefit than harm, few deaths were avoided, especially among women with comorbidities.

Researchers from the National Cancer Institute and the National Institutes of Health used data from the Surveillance, Epidemiology, and End Results (SEER) database and the Breast Cancer Surveillance Consortium to compare breast cancer death, survival, and cost with annual or biennial mammography screening from age 65 years to ages 75, 80, 85, or 90 years. The study adapted a previously published Markov microsimulation model to assess the interventions in women without a previous diagnosis of ductal carcinoma in situ (DCIS) or invasive breast cancer. Results were published Nov. 23 by Annals of Internal Medicine.

Annual mammography beyond age 75 years was not cost-effective, but extending biennial mammography to age 80 years was, with $54,000, $65,000, and $85,000 per quality-adjusted life-year (QALY) gained for women with Charlson comorbidity scores of 0, 1, and 2 or greater, respectively. Extending biennial mammography from age 75 to 80 years averted 1.7, 1.4, and 1.0 breast cancer deaths and increased days of life gained by 5.8, 4.2, and 2.7 days per 1,000 women for with Charlson comorbidity scores of 0, 1, and 2, respectively. Cases of overdiagnosis were double the number of deaths averted from breast cancer. According to the study authors, women considering screening beyond age 75 years need to weigh the harms of overdiagnosis against the potential benefit of averting death from breast cancer.

An accompanying editorial noted that by not considering the cost-effectiveness of breast cancer screening and other tests and treatments, Americans spend more for health care that ends up being rationed.

“It is unlikely that a cost-effectiveness study will lead to deimplementation of annual screening in American women aged 75 years or older,” the editorial stated. “However, such studies might encourage development of models for risk-based screening. Risk-based screening, considering the subject's health status and personal breast cancer risk using polygenic testing, epidemiologic risk calculators, breast density, or a combination, might be an acceptable compromise to our current inefficient practices.”