Receipt of radiotherapy after mastectomy in women with breast cancer: Population-based cohort study in New Zealand

Abstract

Purpose: To investigate the receipt of postmastectomy radiotherapy (PMRT) in breast cancer patients in New Zealand for whom radiotherapy is strongly recommended in current clinical guidelines.

Method: This study involved all women who were diagnosed with primary invasive breast cancer in two health regions, had undergone a mastectomy, and met the "strong recommendation" criteria for PMRT based on New Zealand National Guidelines. We performed logistic regression analyses to identify demographic and clinical factors associated with the receipt of PMRT.

Results: Of the 1455 patients with stage II to III cancers included in this analysis, 1195 (82%) received radiotherapy. The receipt of PMRT decreased with increasing age, and was significantly lower in rural residents, Māori and Pacific women, those with more comorbidity, those who received primary cancer care in a public facility, and those diagnosed with stage III cancer. Although not significant, the receipt was also lower in patients who resided in more deprived neighborhood, and those with comorbidities. The findings restricted to stage III patients (n = 1325), and to those diagnosed since 2010 (n = 422), after the current guidelines were published, which were very similar to the whole cohort.

Conclusion: Disparities exist in the receipt of PMRT in breast cancer patients in New Zealand, underscoring the need for a greater equity focus in management of breast cancer.

Keywords: breast cancer; mastectomy; radiotherapy; utilization.