The patient cohort that needs attention amidst rising bowel cancer rates

The disease is the fourth most common cancer in Australia, it is also our second deadliest cancer. Around one in 16 are expected to develop bowel cancer in their lifetime - a number that has rapidly increased among younger people.

Rates among younger adults have surged by around 266% over the last 40 years. It is now one of the leading causes of death among Australian adults aged 25-54.

Head of the Department of Gastroenterology at Sir Charles Gairdner Hospital Dr Hooi Ee said the proportion of bowel cancers that occur in those under 50 was still relatively low, but the patient cohort needed close attention.

“It has crept up from something like 5-8% to become more like 10-13% of the proportion of total bowel cancers,” he told Medical Forum.

“That increase in proportion is what is of concern, when in fact the rates in older people are actually reducing as a proportion.”

Dr Ee, who is also a clinical professor at UWA, said greater attention needed to be paid to those in their 40s. He said blood in stools, altered bowel habits and abdominal pain could be signs of bowel cancer.

“In general it is found that younger people don’t take these things as seriously, in part because they do not fully realise that cancer can be likely in younger people and they are often at a time in their lives when they are often very busy," he said.

“These health issues don’t seem dominant and they leave it too late. The evidence is that young people present for help to their GPs at later stages than those in the higher age categories.”

Dr Ee said compounding that was the time it takes for bowel cancer to be diagnosed.

“They can be slower to be diagnosed, GPs may think because they are younger cancer is less likely, then when the referral is looked at there might be a longer wait as their age may not suggest they are a priority to be seen," he said.

“So, even once they’ve sought help, they actually wait longer before the point they get diagnosed.”

What to look for

Dr Ee said GPs should keep in mind the same factors they do for older patients and bowel cancer for those under 50.

“The things we know contribute to bowel cancer include dietary factors, not enough consumption of vegetables and fibrous foods, too much consumption of red meat, overconsumption of processed foods, excess weight, inadequate exercise, too much alcohol, cigarette smoking," he said.

“We know in many instances in modern day society these factors have become magnified, so all these things have contributed to this cancer occurring more,” Dr Ee said.

Head of the Department of Gastroenterology at Sir Charles Gairdner Hospital, Dr Hooi Ee.

Screening

Age-specific clinical practice guidelines are currently being developed to provide specific advice around early-onset bowel cancer.

Dr Ee said there was evidence that carrying out screening tests, such as those provided as part of the National Bowel Cancer Screening Program, was beneficial and could be life saving.

The screening program was updated in 2024 to include those aged 45 and over. Previously the eligible age for screening through the program was 50.

However, Dr Ee said while those aged 45 and over are included as part of the cohort targeted by the screening program, they are not as actively focused on as those over 50.

“From 45 to 49 people are now deemed eligible to be in the screening program, but they must request a kit,” Dr Ee said.

Those aged 50 and above have kits mailed out to them every two years.

“How do we detect those people at an earlier stage when there are more treatment options and more curative options available to them? That remains very troublesome and problematic."

Dr Ee said a lot of patients likely presented to GPs with one or more of the three main symptoms.

“The best clue would be if these symptoms are sustained, if something has not gone away and is present for 4-6 weeks, then they must be taken seriously.”

The bigger picture

Dr Ee believes there's a role for governments to play in creating behaviour change around the lifestyle and dietary factors that increase the risk of bowel cancer.

While there was public education about the risks associated with certain lifestyle factors and promoting healthy lifestyle choices, creating behaviour change was far more challenging.

“There are many competing forces, businesses make money out of people eating more junk food, there is a huge amount of marketing directed at consumers and self-interested groups who want their products to be sold, that is what the government is up against.

“Sometimes the only way you can make change is by legislative and regulatory pathways , not simply encouraging people," he said.

Dr Ee pointed to the success of price control measures and cigarette advertisement bans on the rates of smoking in Australia.

CPD opportunities

Chief executive of Doctors For Nutrition Rebecca Stonor said many cases of bowel cancer can be prevented, and outcomes are dramatically improved through early detection.

She said 99% of bowel cancer cases are successfully treated when detected at the earliest stage.

Doctors for Nutrition has released two new courses on preventing bowel cancer, one for health professionals and the other for the general public.

While not associated with the organisation, Dr Ee said evidence-based learning on the topic was welcome.

Doctors For Nutrition champions evidence-based education and resources on optimal human nutrition-led lifestyle medicine strategies to prevent, alleviate, and even reverse chronic diseases.

Preventing Bowel Cancer in Clinical Practice is an online course designed to help doctors understand the evidence behind bowel cancer prevention and learn practical strategies to improve health literacy, support behaviour change, and communicate effectively in everyday clinical practice. 

The general course is designed for patients, to help them understand how everyday lifestyle decisions can influence their risk of bowel cancer.