Objective In the context of a mature mammographic screening programme, the aim of this population-based study was to estimate rates of breast-cancer mortality among participants versus non-participants in Queensland, Australia. Methods The Queensland Electoral Roll was used to identify women aged 50–65 in the year 2000 (n = 269,198). Women with a prior history of invasive or in situ breast cancer were excluded (n = 6,848). The study population was then linked to mammography records from BreastScreen Queensland together with the Wesley Breast Screening Clinic (the largest provider of private screening in Queensland) to establish a screened cohort (n = 187,558) and an unscreened cohort (n = 74,792). Cohort members were matched and linked to cancer notifications and deaths through the state-based Queensland Oncology Repository. Differences in breast-cancer mortality between the two cohorts were measured using Cox proportional hazards regression. Results After 16 years of follow-up, women in the screened cohort showed a 39% reduction in breast-cancer mortality compared to the unscreened cohort (HR = 0.61, 95%CI = 0.55–0.68). Cumulative mortality over the same period was 0.47% and 0.77% in the screened and unscreened cohorts, respectively. Conclusions This study found a significant reduction in breast-cancer mortality for women who participated in mammographic screening compared to unscreened women. Our findings of a breast-cancer mortality benefit for women who have mammographic screening are in line with other observational studies.
Effect of selective serotonin reuptake inhibitors use on endocrine therapy adherence and breast cancer mortality: a population-based study
