Purpose: The number of older patients with breast cancer is rapidly increasing. A previous study showed that between 1990 and 2005, the survival of older patients with breast cancer did not improve in contrast to younger patients. In recent years, scientific evidence in the older age group has increased and specific guidelines for older women with breast cancer have been developed. The aim of this study was to assess changes in survival outcomes of older patients with breast cancer.
Patients and methods: All patients with breast cancer between 2000 and 2017 were included from the Netherlands cancer registry. We assessed changes in treatments using logistic regression. We calculated changes in relative survival as proxy for breast cancer mortality, stratified by age and stage.
Results: We included 239,992 patients. Relative survival improved for patients < 65 for all stages. In patients aged 65-75 years, relative survival did not improve in stage I-II but did improve in stage III breast cancer (RER 0.98, 95% CI 0.96-1.00, p = 0.046). Concurrently, prescription of systemic treatments increased. In patients > 75, relative survival did not improve in patients with stage I/II or stage III disease, nor did treatment strategies change.
Conclusions: This study shows that relative survival of patients aged 65-75 years with advanced breast cancer has improved, and concurrently, prescription of systemic treatment increased. To improve survival of patients > 75 as well, future studies should focus on individualizing treatments based on concomitant comorbidity, geriatric parameters and the risk of competing mortality and toxicity of treatments.
Keywords: Breast cancer; Chemotherapy; Epidemiology; Geriatric oncology; Survival.