Purpose: Cancer remains the most common cause of disease-related death among young people and carries a significant burden. In the absence of prior state-based Australian epidemiological studies, this retrospective cohort study reviewed all cases of invasive cancer diagnosed in Queensland children, adolescents, and young adults (AYAs) (0-39 years) from 1987 to 2016 using the Queensland Oncology Repository (QOR). Methods: Cancers were classified according to Surveillance, Epidemiology and End Results (SEER) AYA site recode. Age-standardized rates (ASRs) were calculated. JoinPoint regression examined trends in ASRs across three age cohorts, for three decades (1987-1996, 1997-2006, and 2007-2016). Results: In total, 3,576 children aged 0-14 years (ASR = 15.2/100,000), 6,441 aged 15-24 years (ASR = 39.3/100,000), and 29,923 (ASR = 122.6/100,000) aged 25-39 years were diagnosed. Incidence increased for female children, and leukemia was the most common diagnosis. For those 15-24 years, incidence increased initially before decreasing and was higher than other nationally reported rates. For those 25-39 years, incidence increased. For the older cohorts, the most common diagnosis was melanoma. All cohorts demonstrated a decline in mortality and improvement in 5-year relative survival, with those 0-14 years demonstrating the greatest gains. The lowest survival for all cohorts was associated with central nervous system tumors. Conclusion: These results highlight areas in need of further investigation to improve survival, reduce the burden of cancer for young people, and aid service delivery. Future studies should focus on cancer biology, early detection, barriers in access to clinical trials, innovative models of care, improved data collection, and patient-reported outcomes.
Keywords: adolescent and young adult oncology; cancer epidemiology; cancer survivorship; childhood cancer.