Background

Liver cancer incidence is increasing in Australia. It is projected to continue rising due to modifiable risk factors and other changes, increasing prevalence of viral hepatitis and metabolic risk factors. While geographical differences in liver cancer incidence and survival have been reported at broad regional levels, these are typically heterogeneous and there is limited information available at the small area level.

This study investigates the spatial patterns of liver cancer incidence and survival across Australia at the small-area level. This is critical for informing local planning, resource allocation and targeted interventions.

Methods

This population-based study is part of the Australian Cancer Atlas. New cases of liver cancer at SA2-level (n = 2,238) were obtained from the Australian Cancer Database and mortality data from Registries of Births, Deaths and Marriages. Incidence and relative survival spatial patterns were modelled using Bayesian spatial Leroux models.

Results

There was strong evidence of spatial variation in the incidence and survival of liver cancer at the small area level (P < 0.001). Incidence rates were higher than the national average in many small areas in Northern and Central regions of Australia, including Darwin, and some areas within southern and eastern state capitals: Sydney, Melbourne, Brisbane and Adelaide. Lower than average incidence rates were observed in many small areas in the Southern and Eastern regions. Survival rates were poorer than the national average in many areas in the Northern and Southernmost regions and higher in some small areas across the Western coastal region. Remoteness and area disadvantage were strongly associated with the proportion of areas having higher incidence and lower survival rates than the national average (P < 0.001).

Conclusion

Our findings demonstrate the need to uncover reasons for this variation, to help inform the development of future interventions aimed at reducing the disparities.