Bowel cancer cases are rising in younger Australians according to new data and oncologists are not sure why.
Bowel Cancer Australia (BCA) says new research published in the Journal of the National Cancer Institute predicts a doubling of early-onset (diagnosed under age 50) rates every 20 years in Australia, Canada, England and US, and for both genders.
The research shows that over the past 10 years, across the four countries, early-onset bowel cancer rates stood at 3.7% annually (3.2% among men, 4.3% for women) but at 7% for young adults aged 20-39 years.
Medical oncologist and BCA spokesman Dr Prasad Cooray says stage IV early-onset bowel cancer needs to be treated as a new disease but efforts are hamstrung by current management models for the diagnosis, treatment and care of younger patients.
“Rates are rising faster in young women who are disproportionately affected by an adverse cancer gene mutation that is biologically aggressive, harder to treat and is often resistant to chemotherapy,” he says.
“An evolving bowel cancer landscape sees us witnessing a significant shift towards younger age at diagnosis and more advanced stage at presentation.”
He says the BCA is seeing an age-related difference in cases — increasing among younger Australians and decreasing in those aged 50-74 years.
“Many younger patients do not fit the traditional risk profiles as they are active, maintain a healthy weight and lack a family history,” Dr Cooray says.
Click here to visit the BCA website.
BOWEL CANCER RISKS
The BCA points to a recent study in the British Medical Journal that says, apart from BMI, risky behaviour such as alcohol use, obesity, physical inactivity, red/processed meat consumption and low fibre intake are unlikely to be major causes of early-onset bowel cancer.
It says rates are increasing in people who do not indulge in the risky behaviour and that no single factor can explain the size or pace of the increasing cases. Suggested factors include genetics, diet, gut bacteria, microbiome changes, antibiotic exposure, ultra-processed foods, sweetened beverages, microplastics and environmental exposures.
“This uncertainty underscores the urgency for research as we still do not fully understand why early-onset bowel cancer is on the rise,” Bowel Cancer Australia CEO Julien Wiggins says.
Australian research into bowel cancer symptoms in primary care, and published in the British Journal of General Practice, found early-onset patients (aged 40-49) had lower investigation rates despite rising cases in younger adults.
“Despite this alarming trajectory, many younger adults continue to be diagnosed with advanced disease due to low clinical suspicion and limited screening options,” Wiggins says.
“Each year, over 1880 young people in their 20’s, 30’s and 40’s will hear the words ‘you have bowel cancer’, the equivalent of 5 new cases each day,” he says.
June has been designated Bowel Cancer Awareness Month, the BCA’s signature event for raising public awareness and funds.
EARLIER HEALTH NEWS: PHA warns of private premiums rise
