A study of gastrointestinal cancer trends over almost three decades has delivered bad news for young men and women aged 18-50.
Australian research into gastrointestinal cancer trends over almost three decades has delivered bad news for men and women under the age of 50.
The Flinders University research published in Cancers, has a revealed a significant increase in the incidence of young-onset [18–50 years] gastrointestinal [oesophageal, stomach, colon and rectum, and pancreas] adenocarcinomas among South Australians– a trend the researchers believe is likely to be replicated around the country.
Lead author, Associate Professor Savio George Barreto, a gastrointestinal and hepato-pancreato-biliary surgeon, says the research highlights the importance of early detection – as well as the need to embrace a healthy lifestyle.
“This paper should not serve to alarm,” he told TMR. “This paper is just intended to raise awareness.”
“For GPs it is an eye-opener,” he said. “It’s important not to dismiss symptoms just because people are young.”
The study has also brought a renewed call from Bowel Cancer Australia to lower the National Bowel Cancer Screening Program start age.
The researchers undertook a cross-sectional analysis of a prospective longitudinal database including all cases of gastrointestinal adenocarcinomas prospectively reported to the South Australian [State] Cancer Registry from 1990 to 2017.
During that period the registry recorded a total 28,566 patients diagnosed with colorectal, pancreatic, stomach or oesophageal adenocarcinomas. Of these, 2129 [7.5%] were aged between 18-50 years. The number of young adults with these cancers progressively increased from 650 in the 1990s [incidence rate of 9.3/100,000 people] to 759 between 2010 and 2017 [incidence rate of 12.89/100,000 people].
“This increased incidence, though noted in both sexes, was more pronounced in males compared to females,” they reported.
“Survival in the young-onset adenocarcinoma cohort was only seen in patients with colorectal cancers, but not oesophagus, stomach and pancreas.”
The trend observed in the young cohort was not mirrored in older individuals aged more than 50 years, the researchers found.
The overall incidence rate for gastrointestinal adenocarcinomas in individuals older than 50 years in South Australia has reduced over the past three decades from 1990–1999 to 2010–2017 [203.04/100,000 to 197.16/100,000], while the overall survival from adenocarcinomas across all subsites improved in the greater than 50-year cohort in the last decade compared to 1990–1999.
Professor Barreto said there needed to be a concerted national effort aimed at determining the sociodemographic factors underlying this disturbing trend.
He said they were not surprised by the results, given the fact that globally, there have been several reports of increasing incidence of early or young-onset cancers. These encompass a spectrum of solid organ cancers such as colorectal cancer [CRC] and adenocarcinomas of the pancreas, breast, ovary, oesophagus and stomach.
Lifestyle factors appear to have play a strong role in increasing people’s risk of gastrointestinal cancer, including obesity and alcohol intake.
Associate Professor Graham Newstead, director of Bowel Cancer Australia, said AIHW data showed bowel cancer had become the deadliest cancer for Australians aged 25-44, and the fifth leading cause of death for the same age group [2017-2019].
Over 86% of people diagnosed with young-onset bowel cancer are symptomatic, and due to the disease often being diagnosed at later stages, treatment options were commonly limited and outcomes poorer.
“As one in 10 new bowel cancer cases now occur in people under the age of 50, the most important message from this article for both GPs and young people is to remain vigilant, recognise and promptly investigate symptoms to rule out bowel cancer as an underlying cause, regardless of age,” he said.
And although the absolute risk of bowel cancer in adults younger than 50 years is low relative to older adults, incidence begins to increase significantly between the ages of 40 and 50, warranting a reduction in the starting age for the National Bowel Screening program.
“Bowel Cancer Australia advocates for lowering the National Bowel Cancer Screening Program start age from 50 to 45 now and to age 40 over time to further reduce incidence and mortality from the disease,” said Professor Newstead.
Co-author Professor Claire Roberts, who leads the university’s Pregnancy Health and Beyond Laboratory [PHaB Lab] said there was a lot of work to be done to further understand this trend.
“We can’t just think about the incidence of cancer, we have to think about the life course,” she said.
She said the higher rates of cancer in men could have a lot to do with the fact that men often don’t seek treatment and may be more likely to be involved in risky behaviour like smoking, alcohol abuse and drug taking. But there might also be genetic and early childhood factors at play.
The impact of obesity on pregnancy and a healthy outcome were also important considerations.
“Over 50% of young women are entering pregnancy obese and [they are] more likely to have pregnancy complications,” Professor Roberts said.
Male obesity also affected pregnancy, creating a higher risk of miscarriage and pre-eclampsia. She said obesity caused epigenetic changes to sperm that could have long-term effects for the health of the child.
