International Study to Explore Causes of Rising Bowel Cancer in Young Adults

April 30, 2026 · KATIE CREMIN

Researchers in Limerick are contributing to a major international study investigating why bowel cancer is increasing among adults under 50.

The Early Onset Colorectal Cancer (ECCE) study, coordinated by the World Health Organisation’s International Agency for Research on Cancer (IARC), brings together teams from 16 countries to explore the causes behind this global trend.

Recent evidence shows that one in ten bowel cancer diagnoses now occurs in people under 50, with rates rising across many countries. The ECCE study aims to understand whether these increases are linked to shared global exposures or to local environmental and lifestyle factors.

Ireland’s involvement will be co‑led by Professor Aedín Culhane, Professor of Cancer Genomics at UL’s School of Medicine, and Professor Christina Fleming, Consultant Colorectal Surgeon at UL Hospital Group and Adjunct Clinical Associate Professor at UL. The research team — including eHealth‑Hub for Cancer postdoctoral researcher Dr Noor Kherrah — will analyse tumour and blood samples to identify DNA “fingerprints” associated with early‑onset disease.

Professor Culhane said the rise in bowel cancer among younger adults is a growing concern, noting that understanding the underlying causes is essential for developing earlier detection and prevention strategies.

Professor Paul Brennan, Head of the Genomic Epidemiology Branch at IARC and global lead for the ECCE study, highlighted Ireland’s unique contribution, explaining that the rise in early‑onset colorectal cancer appears to have occurred later here than in other European countries, offering valuable insight into how risk factors may be changing over time.

Early detection remains key. Bowel cancer is highly treatable when caught early, yet many younger adults are diagnosed at a later stage. In Ireland, bowel screening is currently offered to people aged 57 to 71.

Marking the Visit: A Tree Planted in Recognition of Shared Purpose

During the visit, members of the research team and collaborators planted a tree on campus — a small but meaningful gesture reflecting the growing recognition that cancers, including those rising in younger adults, are increasingly linked to environmental exposures and lifestyle factors. Grounding research in health and sustainability is an important value for the team, acknowledging the connection between the environments we live in and the diseases we seek to understand.

The tree also creates a quiet, restorative space to honour those affected by cancer and to recognise the shared purpose behind this international collaboration.

Pictured: Brendan Muldoon (Bowel Cancer Ireland), Professor Aedín Culhane (UL), John Stack, Professor Paul Brennan (IARC), Dr Noor Kherrah (UL), and Professor Alan Donnelly (UL).