Despite national and global reports of rising incidences of cancer affecting children and young people, new analysis has found rates of childhood cancer have remained unchanged over the past 30 years in South Australia and the Northern Territory.
"This is a reassuring finding and highlights that childhood and young adult cancers have different underlying causes," said lead author Dr Suzanne Mashtoub, who is with the University of Adelaide's Faculty of Health and Medical Sciences and Flinders University's College of Medicine and Public Health.
"A previous analysis of South Australian Cancer Registry data noted significantly increased rates of young-onset adult cancers over the same time period.
"The stable childhood cancer rates led us to infer that perinatal (the period before conception and just after giving birth) factors are less likely, on their own, to play a major role in the rise of young-onset adult cancers."
The recently published study included clinicians and researchers from Flinders Health and Medical Research Institute, the Telethon Kids Institute and the University of Adelaide, as well as leading paediatric oncologists and scientists from the Menzies Research institute in Darwin, UniSA, the Women's and Children's Hospital, the Hebrew University of Jerusalem, and Cedars-Sinai Medical Centre, Los Angeles.
The analysis focused on cancer incidence and survival in children 19 years or younger in South Australia and the Northern Territory from 1990 to 2017.
The authors found cancer incidence had significantly decreased over time amongst non-Indigenous children and remained unchanged amongst Aboriginal and Torres Strait Islander children, with lymphocytic leukemia being the most diagnosed cancer.
Overall survival improved in South Australia and remained steady in the Northern Territory, and while survival rates of Aboriginal and Torres Strait Islander children significantly improved in the last 20 years, they still remained lower than the non-Indigenous cohort.
"If we can identify the risk factors, we could support the development of biomarkers to aid in early detection of cancers, at a stage when cure is possible," said Dr Mashtoub.
Co-author Dr Justine Clark, an Indigenous cancer researcher with the Telethon Kids Institute, said the results highlighted an unacceptable disparity.
"From previous studies, we know that Indigenous families faced with a childhood cancer diagnosis in the NT experience issues related to timely diagnosis and commencement of care, often profound financial and logistical barriers, and issues of cultural safety within cancer services," she said.
"To improve cancer outcomes for Indigenous kids in the NT, the health care system must address the problems raised by Indigenous Australians and their families."
