Tumour samples from the 1950s could reveal why more young people are getting bowel cancer

Bowel cancer diagnosis among younger people is expected to double by 2030

Tumour samples that have been stored for more than 70 years could help solve the mysterious rise of bowel cancer in young people.

Bowel cancer is the fourth most common cancer in the UK, affecting 44,100 people a year, it is also the second leading cause of cancer deaths.

While screening programmes have helped reduce cases in older adults, diagnoses among younger people have been increasing in recent years and are expected to double between 2010 and 2030.

But bowel cancer specimens from the 1950s, stored in the basement of St Mark’s Hospital in London, will be compared with modern-day cancer samples in a pioneering study by researchers at The Institute of Cancer Research (ICR).

The team hopes to uncover how changes in diet, lifestyle and environmental exposures may be driving the rise in early-onset bowel cancer.

Biopsy set in wax stored in the basement of St Marks Hospital in London (The Institute of Cancer Research)

“People in the 1960s lived differently to people today. We believe that the exposome – the changes in diet, lifestyle and environmental factors we are exposed to – is contributing to the increase in cases and deaths from bowel cancers in younger adults,” Trevor Graham, professor of genomics and evolution and director of the Centre for Evolution and Cancer at ICR, London, said.

Holly Masters, 27, is one of a growing number of young people being diagnosed with the disease.

She was diagnosed with stage three rectal cancer more than four years ago after doctors initially diagnosed her with IBS.

“I’d known that something wasn’t right a year before my diagnosis. I had all the symptoms of bowel cancer,” she said.

The actor and access support worker from East Anglia was successfully treated with chemo-radiation, combined chemotherapy and major surgery.

Holly Masters, 27, was diagnosed with stage three rectal cancer over four years ago (The Institute of Cancer Research)

“It did feel unfair to be diagnosed at such a young age. I lost all my innocence and realised how harsh life can be,” she said.

“I now have a stoma, which did take some getting used to and it took me a long time to accept the most difficult consequence-the fear that the cancer will come back. I have to live with the mental and physical effects of my diagnosis for the rest of my life,” she added.

The study, called the “Boomers Project”, will use preserved pathology specimens, which are still suitable for analysis.

Some studies have already shown that early-onset cancers seem to behave more aggressively than bowel cancers in older people. As a result, the outcomes for young patients are often poor, according to ICR.

Scientists have been unable to determine why bowel cancer is becoming more common in young people, but changes in diet, exposure to environmental pollutants such as microplastics and even changes to the microbiome – bugs living in the bowel – are all possible theories.

Project co-lead Professor Kevin Monahan, gastroenterologist and co-director of The St Mark’s Centre for Familial Intestinal Cancer, hopes the historical tumour samples will open a window to new approaches to prevention of bowel cancer in the young (The Institute of Cancer Research)

Environmental exposures, such as an unhealthy diet or smoking, can shape the DNA inside the cancer in unique ways.

The researchers plan to use genome sequencing techniques – including novel approaches developed at ICR – to map how the DNA is altered in the cancer specimens from the 1950s compared to cases from the present day. The comparison will show how environmental exposures have changed over the past decades.

If successful, the project could pave the way for a larger-scale investigation and inform new strategies for prevention, diagnosis, and treatment.

Professor Kevin Monahan, gastroenterologist and co-director of The St Mark’s Centre for Familial Intestinal Cancer, said: “We have a lot to learn about the causes of bowel cancer in young people, and why this has been increasing in recent decades.

“We don’t yet know whether it’s one factor or many ranging from diet and genetics to microplastics and sedentary lifestyles. What’s striking is that many younger patients show no obvious signs of poor health yet are being diagnosed with aggressive forms of bowel cancer. We believe that our unique resource of historical tumour samples at St Mark’s Hospital will open a window to new approaches to prevention of bowel cancer in the young.

“A healthy diet and regular exercise, as well as speaking to your GP if you have new bowel symptoms such as bleeding from the back passage, or a change in how often you open your bowels, remain some of the most important ways of reducing the risk of bowel cancer.”