Background: Indigenous Australians with cancer in general receive less cancer treatment, take longer to receive their treatment, and have poorer cancer outcomes than non-Indigenous Australians; however, the comparative outcomes for Indigenous women with breast cancer are largely unknown. We have therefore compared diagnosis, treatment, and presence of comorbidity in Indigenous and non-Indigenous Australian women diagnosed with breast cancer.
Methods: Through a matched cohort design we compared all Indigenous women (n=110) treated in Queensland public hospitals (1998-2004) to a frequency-matched (age, place of residence) random sample of non-Indigenous women (n=105). Clinical data were abstracted from records at public hospitals to a standard form.
Results: At diagnosis, Indigenous women had an average age of 54 years, were more likely to be highly socioeconomically disadvantaged (43% vs. 20% for non-Indigenous women; p<0.01), to have serious comorbidity (diabetes, cardiovascular disease; p<0.01), and more advanced disease than non-Indigenous women (regional/metastatic spread 51% vs. 36%, respectively; p=0.03). There was no difference in the histological types of tumours (p= 0.46), the proportions of oestrogen and progesterone receptor positive tumours (approximately 80%; P=0.92 and 70%; p=0.76 respectively), in time from diagnosis to treatment (p=0.26), treatment completion rates (p>0.05), mode of treatment (lumpectomy vs. mastectomy; p=0.17), or rates of tamoxifen use (p=0.17) between groups.
Conclusions: In Queensland, Indigenous women with breast cancer generally received comparable treatment to their non-Indigenous counterparts. Differences in comorbidity and stage at diagnosis between the two groups reinforce the need for early detection and improved management of co-existing disease in Indigenous women with breast cancer.