Health benefits and harms of mammography screening in older women (75+ years)-a systematic review.

BACKGROUND:There is little evidence on the balance between potential benefits and harms of mammography screening in women 75 years and older. The aim of this systematic review was to synthesise the evidence on the outcomes of mammography screening in women aged 75 years and older. METHODS:A systematic review of mammography screening studies in women aged 75 years and over. RESULTS:Thirty-six studies were included in this review: 27 observational studies and 9 modelling studies. Many of the included studies used no or uninformative comparison groups resulting in a potential bias towards the benefits of screening. Despite this, there was mixed evidence about the benefits and harms of continuing mammography screening beyond the age of 75 years. Some studies showed a beneficial effect on breast cancer mortality, and other studies showed no effect on mortality. Some studies showed some harms (false positive tests and recalls) being comparable to those in younger age-groups, with other studies showing increase in false positive screens and biopsies in older age-group. Although reported in fewer studies, there was consistent evidence of increased overdiagnosis in older age-groups. CONCLUSION:There is limited evidence available to make a recommendation for/against continuing breast screening beyond the age of 75 years. Future studies should use more informative comparisons and should estimate overdiagnosis given potentially substantial harm in this age-group due to competing causes of death. This review was prospectively registered with PROSPERO (CRD42020203131).