Individual Abstract within a Delegate Designed Symposium 2025 Joint Meeting of the COSA ASM and IPOS Congress

Early onset cancers: what the Australian data tells us (126356)

Vivienne Milch 1 2 , Debra Hector 1 , David M Roder 1 , Cathelijne (Cat) van Kemenade 3 , Carolyn Der Vartanian 1 , Sarah McNeill 1 , Tyler Ho 1 , Ashleigh R Sharman 1 , Claire Howlett 1 , Dorothy Keefe 1 4 5
  1. Cancer Australia, Surry Hills, NSW, Australia
  2. School of Medicine, The University of Notre Dame, Sydney, NSW, Australia
  3. The Sax Institute, Sydney
  4. Caring Futures Institute, Flinders University, Adelaide, South Australia, Australia
  5. School of Medicine, University of Adelaide, Adelaide, South Australia, Australia

OBJECTIVES/PURPOSE

Australia has the highest age-standardised incidence rate of early-onset cancers (EOC), or cancers diagnosed in people aged 20-49 in the world. This increasing incidence is also reflected in other developed countries. Cancer Australia sought to quantify the changing rate of EOC and identify evidence on emerging risk factors associated with increasing incidence, to identify research gaps and understand national policy implications.

SAMPLE AND SETTING

Not applicable for desktop literature review.

PROCEDURES

Data and statistics were sourced from the Cancer data in Australia (CdiA), Australian Institute of Health & Welfare, and the Global Cancer Observatory. Peer-reviewed publications related to the epidemiology of early-onset cancers in Australia and globally were sourced via PubMed and Google Scholar, with the majority of data sourced from the Global Cancer Observatory (GLOBOCAN and the Cancer Incidence in Five Continents (CI5) databases). A systematic review was conducted using PubMed and Embase with 1,225 peer-reviewed papers screened at the title and abstract level. A search was also conducted for recent epidemiological observational studies.

RESULTS

Between 2000-2020, the incidence rate for colorectal cancer increased among Australians aged 0-49 years but decreased among Australians aged 50+ years. Early-life dietary patterns and gut microbiome disturbances appear to play a role in early onset colorectal cancer, while in breast cancer the convergence of high genetic risk with adverse lifestyle effects such as alcohol use are known contributors.

CONCLUSION AND CLINICAL IMPLICATIONS

Cancer Australia will continue investigating risk factors of EOC, which are likely a complex interplay of genetic susceptibility, lifestyle modifications, and environmental exposures. Cancer Australia will also keep abreast of emerging data and provide guidance on reducing the impact of EOC on Australians affected by cancer. Findings will inform future research investment, allocated through a competitive research grants program focussed on emerging cancer research priorities, commencing in 2025-26.