Breast cancer is the largest contributor to cancer incidence and cancer mortality in women worldwide. As people in Western societies are living longer, there will be an increase in the proportion of older women with breast cancer in upcoming years. Older women with breast cancer often have comorbidities and functional limitations, resulting in an increased risk of adverse outcomes and side effects from breast cancer treatment. Also, previous studies have shown that breast cancer specific mortality increases with age. It has been assumed that diagnosis at an earlier stage through screening programmes could improve the prognosis of breast cancer and may therefore be beneficial for older women. Several current guidelines recommend breast cancer screening with mammography for women aged up to 75 years, and in the Netherlands in 1998, the upper age limit of the mass screening programme was extended from 69 to 75 years.