Surgical and radiotherapy patterns of care in the management of breast cancer in NSW and ACT Australia.

Introduction: This study aims to report on the surgical and radiotherapy patterns of breast cancer care in New South Wales (NSW) and Australian Capital Territory (ACT) in Australia, to identify factors that impact on utilisation of evidence-based treatment and to report on the overall survival (OS) rate and the influencing factors on OS.

Methods: Cancer registry data linked to hospital records for all patients with breast cancer diagnosis in NSW and ACT between 2009 and 2014 were used to calculate rates of breast conserving surgery (BCS), mastectomy, sentinel lymph node biopsy (SLNB), axillary lymph node dissection (ALND) and radiotherapy. Multivariate analysis used to identify factors that led to variations in care. 5-year OS was calculated and cox regression model assessed factors that influenced survival.

Results: Data for 30,337 patients were analysed. BCS and mastectomy rates were 64% and 36%, respectively. The SLNB, ALND and ALND after SLNB rates were 61.5%, 32.1% and 6.4%, respectively. Radiotherapy was utilised in 63%. Younger age, socio-economic disadvantage, longer distance to a radiotherapy facility and overseas place of birth were factors that predicted for increased rates of mastectomy and ALND. Radiotherapy was more likely to be utilised in later years of diagnosis, patients between 40-69 years old, and those who lived in major cities and closer to a radiotherapy facility. 5-year OS was 80.5%. Older patients, the socioeconomically disadvantaged and those advanced tumours had worse survival.

Conclusion: Variations in breast cancer care continue to exist in certain patient groups that we identified. Targeted strategic planning and further research to identify other drivers of existing disparities remain a priority.