Rates of bowel cancer in young Australians is the highest in the world

Someone born in 1990 in Australia is three times more likely to get bowel cancer than a Baby Boomer — Why?

Phillip Mellen was about to cancel his colonoscopy appointment before something told him to go through with it.

He’d been having abdominal painand blood in his stool but in the time between his GP appointment and the gastroenterologist appointment, his symptoms had all cleared up.

“A colonoscopy is not exactly a pleasant experience … so I was really humming and ahhing about whether or not I wanted to actually go,” the 37-year-old told The Advertiser.

“I figured I’ll go through to be safe rather than sorry.”

Following his appointment his doctor said they came across a tumour — and a few days later he was told he had stage three bowel cancer.

“Everything changed from that moment,” the Lockleys man said.

Mr Mellen is one in 28,265 cases of early-onset bowel cancer case over the past 30 years.

Australia is now the country with the highest rate of early-onset bowel cancer in the world, with incidence having increased by eight per cent per year.

Phillip Mellen now lives with stage four bowel cancer. Picture: Emma Brasier

Mr Mellen had surgery to resect his bowel and remove the cancerous tumour within a week of discovering his diagnosis.

“The initial response is a bit of disbelief,” he said.

Then after he had time to recover he underwent 12 rounds of chemotherapy.

For around two years he monitored his health with medical professionals, undergoing appointments, scans and tests to see if he was in the clear.

“When people finish chemotherapy treatment there’s this idea of wanting to get back on with life as per normal,” Mr Mellen, who is a research scientist, said.

“You don’t want things to be defined by your cancer experience but at the same time, it leaves an indelible mark and changes the way that you do things.”

For Mr Mellen he was left with peripheral neuropathy in his hands and feet and fatigue.

In March this year, he received heartbreaking news that the cancer had returned and was stage four.

Mr Mellen said, as a research scientist he approached his own treatment perhaps differently to other patients.

“(Chemotherapy) was a course of action that improved bad numbers to be better numbers but by no means was it a guarantee of things not coming back,” he said.

“I was reasonably emotionally prepared for that eventuality but I mean, it’s still unfortunate and difficult news to take.”

Professor Mark Jenkins from the University of Melbourne is researching early on-set bowel cancer. Picture: Supplied

Professor Mark Jenkins, who conducted the research at Melbourne University with his colleague Aaron Meyers, said “our inability to halt the rising burden of early-onset bowel cancer over the last thirty-years has resulted in over 4300 excess cases being diagnosed among young Australians”.

Their research found people born in 1990 were two to three times more likely to be diagnosed with bowel cancer than someone born in 1950.

“We don’t know why but it gives us a clue as to what the causes might have been,” Professor Jenkins said.

“If we know what is more common in the 1990s in our environment or lifestyle or the way we take medication or treat things — if we know there’s something much more common in the 1990s than the 1950s it might give us a clue as to what might have caused this increase.”

Bowel Cancer Australia CEO, Julien Wiggins, said in 2024, bowel cancer is estimated to be the deadliest cancer for men and the second deadliest for women under 50.

“This risk of being diagnosed before age 40 has more than doubled since 2000, and one-in-nine new bowel cancer cases now occur in people under age 50,” he said.

Originally published as Rates of bowel cancer in young Australians is the highest in the world