Cancer survival differentials for Aboriginal and Torres Strait Islander peoples in Queensland: the impact of remoteness.

ABSTRACT

PURPOSE: In Australia, Aboriginal and Torres Strait Islander peoples (First Nations population) often have low overall cancer survival, as do all residents of geographically remote areas. This study aimed to quantify the survival disparity between First Nations and other Queenslanders for 12 common cancer types by remoteness areas. METHODS: For all Queensland residents aged 20-89 years diagnosed with a primary invasive cancer during 1997-2016, we ran flexible parametric survival models incorporating age, First Nations status, sex, diagnosis time period, area-level socioeconomic status, remoteness categories and where appropriate, broad cancer type. Three survival measures were predicted cause-specific survival, survival differences and the comparative survival ratio, each standardised to First Nations peoples' covariate distributions. RESULTS: The standardised five-year cause-specific cancer survival was 60% for urban First Nations and 65% for other Queenslanders, while remote residents were 54% (First Nations) and 58% (other). The absolute survival differential between First Nations and other Queenslanders was often similar, regardless of remoteness of residence. The greatest absolute difference in five-year standardised cancer survival was for head and neck cancers, followed by cervical cancer. The five-year comparative survival ratio (First Nations other Queenslanders) for urban cancer patients was 0.91 (95% CI 0.90-0.93), similar to outer regional, inner regional and remote areas. The greatest comparative survival differential was for oesophageal cancer. CONCLUSION: First Nations' survival inequalities are largely independent of geographical remoteness. It remains a priority to determine the contribution of other potential factors such as the availability of culturally acceptable diagnostic, management and/or support services.