Long-term survival outcomes following breast cancer surgery in Western Australia

BACKGROUND: Mortality rates from breast cancer are stabilizing or falling in many developed countries including Australia, however, survival outcomes are known to vary by social, demographic and treatment related factors. The aim of the present study was to investigate how hospital, social and demographic factors were associated with survival outcomes from surgically treated breast cancer for all women living in Western Australia. METHODS: The WA Data Linkage System was used to access hospital morbidity, death and cancer information for all women diagnosed with invasive breast cancer in Western Australia 1982-2000. Relative survival and Cox proportional hazards regression analyses were used to identify social, demographic and hospital factors associated with an increased risk of dying from breast cancer or dying from any cause. RESULTS: Survival outcomes improved in all women diagnosed in more recent calendar periods. However, a significantly increased risk of dying was observed for women who underwent initial surgical treatment in regional public hospitals outside of the state capital, Perth. Consistent with other reports, women aged greater than 80 years and younger than 35 years at diagnosis also had poorer survival outcomes. Residential location, socioeconomic status and race were not associated with survival after adjusting for treatment, health and hospital related factors. CONCLUSIONS: Despite overall improvements in survival of women diagnosed with breast cancer in Western Australia, initial surgical treatment in public hospitals outside of Perth was associated with significantly poorer outcomes.