The impact of genetics and the environment on cancer risk in Indigenous Australians: a narrative review.

Aboriginal and Torres Strait Islander (hereafter respectfully named Indigenous) Australians are diagnosed with some cancers substantially more frequently than non-Indigenous Australians implying a different risk factor landscape. Additionally, poorer outcomes for certain cancers are exacerbated by lower cancer screening rates and later diagnoses compared to non-Indigenous Australians. An improved understanding of cancer causation would allow better shaping and targeting of screening programs for those at the highest risk. A narrative review of relevant environmental and genetic risk factors for various cancers in Indigenous populations was undertaken. Research databases were interrogated in June 2024, with information extracted. Further peer-reviewed and grey literature was identified by specific searchers and citation snowballing. The results show that many distinct risk factors exist in environmental, sociocultural, educational, behavioural and metabolic domains; these complex and frequently interacting risks include direct and indirect social and cultural factors. Identified gaps include limited published literature on the genetic determinants of cancer, decreased levels of effective cancer surveillance for Indigenous Australians, a paucity of culturally appropriate cancer health education programs for both Indigenous community members and health providers, and the historical absence of an Indigenous Australian focus and contribution to research on cancer causation. Indigenous Australian co-designed research is needed to address the gaps contributing to cancer prevention and screening development. Empowerment of national Indigenous Australian leadership in partnership with researchers and service providers is needed to develop tailored health interventions and reduce the existing and future challenges of the cancer burden on Indigenous communities.