Breath Research Narrow Validation for Gastrointestinal Cancer Detection

The investigators of this study are developing a simple breath test to help detect gastrointestinal (gut) cancers earlier, including cancers of the oesophagus (food pipe), stomach, pancreas, liver and bowel. These cancers often cause non-specific symptoms that are similar to benign conditions, making early diagnosis difficult. Delays between the onset of symptoms and referral for a diagnostic test such as an endoscopy or a scan, can allow the cancer to progress. The breath test detects small molecules called volatile organic compounds (VOCs) that are released in exhaled breath. Some of these VOCs are strongly associated with these cancers and may help identify high-risk patients who require urgent investigation. In practice, patients who come to their GP with concerning symptoms will be offered the breath test. If the test is positive, patients can be referred promptly for a diagnostic test, while those with a negative result can be reassured and offered re-testing if symptoms persist. Earlier diagnosis could improve access to curative treatment while reducing unnecessary invasive investigations. Previous studies have identified a panel of VOCs that appear to distinguish patients with gastrointestinal cancers from those without cancer. This study aims to confirm these findings in a new group of participants to determine whether the same biomarkers can be reliably identified. Participants will provide a breath sample, usually before a hospital procedure they are already scheduled to undergo, and complete a short questionnaire about their medical history and medications. Some participants will also be asked to drink a nutritional supplement before providing a second breath sample. The results will help determine whether the breath test is reliable enough for further clinical evaluation