Quantifying the Diagnosis and Survival of Early Onset Bowel Cancer Among First Nations Peoples in Queensland, Australia

The incidence of early-onset bowel cancer (EOBC) is increasing in Australia and globally. However, the burden of EOBC among First Nations Australians is rarely determined. This study aimed to quantify the diagnosis and survival rates of EOBC among First Nations Peoples in Queensland, Australia.

CancerCostMod, a linked administrative dataset of patients diagnosed with cancer in Queensland from 1st July 2011 to 30th June 2015, was used. EOBC was defined as a diagnosis of bowel cancer (i.e., colon, rectosigmoid, or rectal cancer) at 18-49 years of age. A multivariable logistic regression analysis was employed to determine the association of Indigenous status and other factors with a diagnosis of EOBC. Five-year survival rates were used to estimate the survival rate.

Of 11,702 bowel cancer cases, 9.2% (95% CI: 8.7%-9.7%) were EOBC, with 19% among First Nations peoples and 9% among Non-First Nations. First Nations Australians had 2.6 times the odds of EOBC diagnosis (95% CI: 1.7-4.0) compared with Non-First Nations Australians. Overall, EOBC patients showed a significantly higher 5-year survival rate of 77% compared with 60% for late-onset bowel cancer patients. However, First Nations EOBC patients showed a lower 5-year survival rate (73%) than Non-First Nations EOBC patients (77%).

First Nations Australians have more than double the diagnosis rates and lower 5-year survival for EOBC compared to Non-First Nations. Whilst the recent lowering of the age eligibility for the National Bowel Cancer Screening Program is a beneficial strategy to address the increasing incidence of EOBC, special consideration should be given to addressing the higher diagnosis rates and lower survival among First Nations Australians. This study raises the potential for further lowering the age eligibility for First Nations Australians to ensure younger First Nations Australians can access screening for earlier detection, thereby improving their survival from bowel cancer.