Background: Australian Aboriginal and Torres Strait Islander women have both higher incidence and mortality from gynaecological cancers than non Indigenous women but little is known about how survival compares between the two groups. We therefore aimed to compare survival of Indigenous and non-Indigenous gynaecological patients in Queensland and identify factors that may explain potential discrepancies.
Methods: All Indigenous women diagnosed with a gynaecological cancer, including uterine, cervical, ovarian and others, between 1998 and 2004 and treated in a Queensland public hospital (n=137) were compared to a random sample of non-Indigenous gynaecological cancers patients, matched on age, remoteness of residence and cancer type (n=120). Data was abstracted from public hospital records and the National Death Index. Time to event analysis was conducted using Cox Regression models to describe survival differences between Indigenous and non-Indigenous women, unadjusted and adjusted for key factors.
Results: Indigenous women were more likely to have regional or metastatic spread of disease at diagnosis (52% v. 35%, p=0.02), more likely to have a comorbidity at diagnosis (51% v. 21%, p<0.001), and less likely to undergo cancer treatment (91% v. 98%, p=0.01) compared to non-Indigenous women. When considering only cancer-related deaths, Indigenous women were 50% more likely to die during the study period (HR 1.5, 95% CI 1.0-2.3); however the ratio decreased when adjusted for stage, comorbidities, and treatment (HR 1.1, 95% CI 0.7-1.7). Results were similar when considering all-cause deaths (unadjusted HR 1.7, 95% CI 1.1-2.5 and adjusted HR 1.2, 95% CI 0.7-1.8).
Conclusions: Indigenous women diagnosed with gynaecological cancer have poorer survival rates than their non-Indigenous counterparts. This was explained by differences in stage of disease, comorbidities and uptake of cancer treatment.