A study of more than 50,000 women found that continued breast cancer screening after age 70 was associated with a greater incidence of cancer that likely would not have caused symptoms in the patient’s lifetime. These findings suggest that overdiagnosis may be common among older women who are diagnosed with breast cancer after screening. The study is published in Annals of Internal Medicine.
Researchers from the Yale School of Medicine conducted a retrospective cohort study of 54,635 women aged 70 years and older who had been recently screened for breast cancer. The authors found that the risk of overdiagnosis increased significantly with age. They report that among women aged 70 to 74, up to an estimated 31 percent of breast cancer found among screened women was over diagnosed. In women aged 74 to 84 years, up to 47 percent of breast cancer found among screened women was over diagnosed. They also found that the risk of overdiagnosis was highest in women aged 85 years and older, who experienced up to a 54 percent rate of overdiagnosis. The authors note that they did not see statistically significant reductions in breast cancer-specific death associated with screening. These findings suggest that overdiagnosis should be explicitly considered when making screening decisions, along with considering possible benefits of screening.