London, UK – In a dusty hospital basement on the outskirts of London, over 100 years of medical history lies preserved in tens of thousands of specimen boxes. Neatly arranged in rows, these tumour and tissue samples some dating back to the early 20th century may hold vital clues to one of today’s most perplexing medical mysteries: the rising number of younger people being diagnosed with bowel cancer.
A Century of Medical History
The archive belongs to St Mark’s Hospital, the UK’s national bowel hospital in northwest London. Preserved in formaldehyde and paraffin wax, the specimens were collected from patients treated across decades.
In January 2026, researchers from St Mark’s and the Institute of Cancer Research, London launched a groundbreaking study comparing tumours from the 1960s with those of today.
“We want to think about whether we can convert the suffering that they went through decades ago into a new hope for their grandchildren and great grandchildren,” said Kevin Monahan, consultant gastroenterologist and co-lead of the project.
Rising Cases Among the Young
Doctors worldwide have been puzzled by the sharp increase in bowel cancer among younger patients.
- According to Bowel Cancer UK, cases in people under 50 have risen by over 50 percent in the past 25 years.
- More than 2,600 cases are diagnosed annually in younger age groups, out of nearly 44,000 cases across all ages.
- Research published in the British Journal of Surgery (2020) described an “exponential increase,” a trend echoed in European and American studies.
Unlocking Clues Through DNA
The study aims to map how DNA in tumours has changed over time. Co-study lead Trevor Graham explained that by sequencing DNA and applying techniques unavailable even five years ago, researchers hope to identify what is driving modern-day cases.
Monahan’s own hunch points to a subtype of E. coli bacteria in the gut.
“This bacteria may be carcinogenic, and the mark of that carcinogen in DNA has been found in younger people with bowel cancer under 50, four times as commonly as it has been in people with all cancer after the age of 50,” he said.
A Saved Legacy
Remarkably, the archive was nearly destroyed a decade ago, destined for incineration before medics intervened to preserve it. Among its treasures is a ledger from 1919, filled with neatly typed medical notes and hand-drawn specimen illustrations.
Lifestyle, Environment, and Unanswered Questions
Changes in diet, lifestyle, and exposure to environmental pollutants such as microplastics have all been suggested as possible causes of the rise in cases, but definitive proof remains elusive.
For younger patients, the diagnosis is often devastating. Many ask “Why me?” despite living healthy lifestyles. Monahan stresses that while exercise and diet are important for general health, bowel cancer can strike regardless.
“It’s nothing to do with what you have done,” he reassures patients.
Looking Ahead
If caught early, 90 percent of bowel cancer cases can be successfully treated, according to the NHS. The current research project is expected to report findings within three years, offering hope that the archive’s legacy will help unlock answers for future generations.
