Scientists are warning of a surge in early-onset cancers among young Australians, with cases of bowel cancer in people under 50 more than doubling over the past two decades. A 2021 report from the Australian Institute of Health and Welfare found that the incidence of bowel cancer in 20- to 39-year-olds rose from 4.4 to 10.3 cases per 100,000 people between 2000 and 2020. Thyroid cancer rates also jumped from 6.5 to an estimated 10.9 cases per 100,000 over the same period.
Globally, rates of certain cancers have increased markedly in younger people since the 1990s, prompting some researchers to label early-onset cancer as “an emerging global epidemic”. A review of cancer registry data published last year found that the incidence of 14 cancers, including colorectal, oesophageal, endometrial, gall bladder, kidney and thyroid, had risen significantly in under-50s in Australia, New Zealand, the US, England and Wales, Canada and South Korea. The study observed a birth cohort effect, with successive age groups facing higher cancer risk than earlier generations.
Anthony Ellison, a personal trainer, was diagnosed with stage 4 bowel cancer at age 39 after experiencing persistent diarrhoea. “Cancer obviously wasn’t on the radar, nor was any sort of chronic illness,” he said. Similarly, Stephanie Bansemer-Brown was told she was “too young” for cancer when she requested a colonoscopy at age 41, despite symptoms including blood in her stool and bloating. She was eventually diagnosed with stage 3 bowel cancer.
Scientists hypothesise that lifestyle changes and increased exposure to risk factors in early life and young adulthood may be driving the rise, but unanswered questions remain. Dr Savio Barreto of Flinders University noted that in South Australia, young males had a higher incidence of gastrointestinal adenocarcinomas. Dr Eleonora Feletto of the Daffodil Centre emphasised that age remains a major risk factor, but younger patients often face diagnostic delays because cancer is still seen as a disease of old age.
