Bowel cancer cases spiking

Unknown environmental factors are causing bowel cancer rates to rapidly accelerate in young people, according to new research.

The research, carried out at the University of Otago, Christchurch, shows that the rates of early onset colorectal cancer (EOCRC) in people under 50 is increasing by 26% every decade.

Researchers said that because the increase was so rapid, it was due to environmental factors that were not yet known, rather than genetics.

New Zealand already has one of the highest rates of bowel cancer in the world, with more than 3000 people diagnosed every year.

The study’s data modelling projects that if the rapid increase continues into 2040, there could be 524 cases of early onset colorectal cancer each year in New Zealand, more than double the number in 2020.

Elise Johns was 36 and pregnant when she was diagnosed with stage three bowel cancer last year.

She was a personal trainer, lived on a farm in Culverden, about an hour’s drive from Christchurch, and never got sick. So being told she had the disease was “bizarre”, she said.

Getting a diagnosis wasn’t an easy road.

She saw a doctor, was told she was too young to have cancer, and was “fobbed off” for a colonoscopy by her hospital. She decided to pay extra to see a specialist.

It took her five months, $2000 and an MRI to be told she had the disease.

“If I didn’t advocate for myself and pay for a specialist, I would probably still be waiting for a colonoscopy. I might have been stage four by now,” she said.

Dr Oliver Waddell, lead author of the study, said that other than accelerating rates of EOCRC, the study showed that for patients under 50, one in three were latestage cancers, and they experienced high delays to being diagnosed.

“Young people are more likely to wait for longer times with symptoms, thinking they aren’t something to worry about. But sometimes when they do see a doctor, the doctor may think they are too young to have cancer, and refer them on,” Waddell said.

“We need to increase awareness in the medical profession that rates of bowel cancer in young people are increasing, and therefore anyone who comes in with symptoms, we need to work them up.”

Another key finding shows that the rate of bowel cancer in young Māori is increasing even more, with a 36% increase each decade.

Waddell said this was particularly concerning, as Māori were more likely to have latestage cancer when diagnosed, and were more likely to die from disease.

He said the pattern of the disease was also changing. “Previously, it was only in the end of the colon or in the rectum, but now we’re seeing significant increases everywhere in the bowel, which is new.”

Medical adviser to Bowel Cancer New Zealand and co-author of the study, Frank Frizelle, said 42 other countries had started compiling data, and every one showed that bowel cancer in young people was “accelerating”.

Along with Waddell, he is calling for the screening age in New Zealand to be lowered to 45, a change other countries are starting to make.

The current screening age for bowel cancer in New Zealand is 60 for non-Māori and 50 for Māori. More people would continue to be diagnosed and die from the disease if the age wasn’t decreased, Frizelle said.

“Australia is down to 50 already, and you can go down to 45 if you see your GP.

“They recognise this is a problem, but New Zealand doesn’t seem to be able to do that.”

Waddell said prioritising lowering the screening age, and educating doctors and young people, needed to be a priority.

He encouraged New Zealanders to keep an eye on their symptoms and to see a doctor if they were worried. Full symptoms can be found on Bowel Cancer New Zealand’s website.