An observational study in Oesophageal Squamous Cell Carcinoma, Oesophageal Adenocarcinoma and Gastric Adenocarcinoma, sponsored by Imperial College London. Recruiting at 6 sites in United Kingdom. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-10-22.
Sponsored by Imperial College London · Observational
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
In the United Kingdom, approximately 75,000 patients are diagnosed with, and 45,000 patients die from, the five major gastrointestinal cancers (oesophageal, gastric, pancreatic, liver and colorectal) each year. Early-stage disease is commonly associated with non-specific symptoms that mimic benign conditions.
Diagnosing cancer at an advanced stage limits curative treatment options. The overall 5-year survival for oesophageal, gastric, pancreatic, liver and colorectal cancer remains poor (15.9%, 20.7%, 9.0%, 12.6% and 50.7% respectively) and is strongly dependent on the stage at diagnosis. Currently, only 14.1%, 19.1%, 14.8%, 13.6% and 37.3% of oesophageal, gastric, pancreatic, liver and colorectal cancers are diagnosed at an early stage.
Earlier detection improves survival and quality of life by increasing access to curative treatment, enabling minimally invasive surgery, shortening hospital stays and facilitating an earlier return to normal activities. Avoiding unnecessary invasive investigations also reduces patient anxiety and the risk of procedure-related complications. Streamlining the diagnostic pathway has the potential to reduce unnecessary investigations and waiting times for endoscopy and cross-sectional imaging.
To address the challenge of earlier detection, the investigators of this study have developed a series of non-invasive breath tests that use volatile organic compound (VOC) analysis to identify symptomatic patients at risk of gastrointestinal cancers. In the future, a GP seeing a patient with symptoms suggestive of gastrointestinal cancer could request a breath test to help guide onward referral for endoscopy or imaging. Such tests could benefit patients with non-specific symptoms who do not currently meet existing referral criteria.
As part of this research programme, the investigators have conducted several clinical studies to identify VOC biomarkers associated with gastrointestinal cancers and develop VOC-based clinical prediction models (CPM) for the following cancers:
The aim of the BRAVE study is to externally validate these VOC-based clinical prediction models in an enriched population, providing confidence in their diagnostic performance before progressing to the next phase of blinded validation studies.
675 studies on the registry are indexed under Esophageal Squamous Cell Carcinoma; 267 are open to participants now.
This study's planned enrollment of 1,000 is above the median of 247 across 86 observational studies indexed under Esophageal Squamous Cell Carcinoma.
Browse Esophageal Squamous Cell Carcinoma studies →Imperial College London is the lead sponsor of 843 studies on the registry; 180 are open to participants now.
Of its 9 completed or terminated interventional studies of FDA-regulated products, 6 (67%) have results posted.
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Adult Participants who meet the eligibility criteria and are being referred for further specialised investigations within the NHS.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Adult participants ≥ 18 years old who meet at least one of the following criteria
Colorectal arm:
Pancreatic arm:
Oesophagogastric arm:
Oesophageal squamous arm:
Liver arm:
Control: Non-specific abdominal symptoms with a radiologically-normal liver
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
The diagnosis was confirmed by looking at a sample under a microscope: tissue from a biopsy or surgery (histology), or cells from a fluid or needle sample (cytology).
Your pathology report is the document that shows this.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Histologically or cytologically confirmed
The diagnosis was confirmed by looking at a sample under a microscope: tissue from a biopsy or surgery (histology), or cells from a fluid or needle sample (cytology).
Your pathology report is the document that shows this.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Cases will be patients with histology-confirmed, treatment naïve oesophageal (OAC) or gastric adenocarcinoma (GAC) and controls will be patients who have a normal upper GI tract or benign condition as diagnosed on the reference test (upper GI endoscopy). All eligible patients will be invited to participate. Participants will attend a one off research visit, after having fasted for 6 hours (water permitted) and sign a consent form. They will rinse their mouth with water, provide a baseline breath sample and consume an oral stimulant drink (a nutrient supplement). A further breath sample will be collected after 15 minutes, and an additional environment sample will also be collected. Participants will answer questions about their medical and drug history.
Cases will be patients with histology-confirmed, treatment naive Oesophageal Squamous Cell Carcinoma (OSCC) and controls will be patients who have a normal upper GI tract or benign condition as diagnosed on the reference test (upper GI endoscopy). All eligible patients will be invited to participate. Participants will attend a one-off research visit, after having fasted for 6 hours (water permitted) and sign a consent form. They will rinse their mouth with water and provide a breath sample. An additional environment sample will also be collected. Participants will answer questions about their medical and drug history.
Cases will be patients with histology-confirmed, treatment naïve pancreatic ductal adenocarcinoma (PDAC) and controls will be patients with non-specific abdominal symptoms and a radiologically-normal pancreas as diagnosed on the reference test (ultrasound, MRI, CT, PET-CT and endoscopic ultrasound). All eligible patients will be invited to participate. Participants will attend a one-off research visit, after having fasted for 6 hours (water permitted) and sign a consent form. They will rinse their mouth with water and provide a breath sample. An additional environment sample will also be collected. Participants will answer questions about their medical and drug history.
Cases will be patients with histology-confirmed, treatment naïve hepatocellular carcinoma (HCC) and cholangiocarcinoma (CCC) and controls will be patients with non-specific abdominal symptoms with a radiologically-normal liver as diagnosed on the reference test (ultrasound, MRI, CT and PET-CT). All eligible patients will be invited to participate. Participants will attend a one-off research visit, after having fasted for 6 hours (water permitted) and sign a consent form. They will rinse their mouth with water and provide a breath sample. An additional environment sample will also be collected. Participants will answer questions about their medical and drug history.
Cases will be patients with histology-confirmed, treatment naïve colorectal adenocarcinoma (CRC) and controls will be patients with non-specific abdominal symptoms with a normal lower GI tract or benign condition of the colon as diagnosed on the reference test (colonoscopy). All eligible patients will be invited to participate. Participants will attend a one-off research visit, after having fasted for 6 hours (water permitted) and sign a consent form. They will rinse their mouth with water and provide a breath sample. An additional environment sample will also be collected. Participants will answer questions about their medical and drug history.
To validate and refine a series of breath tests to detect the following conditions: CRC, PDAC, OGC, OSCC, HCC and CCC
Estimation of sensitivity, specificity and numbers of false positives (with 95% confidence intervals) for breath tests to detect CRC, PDAC, OGC, OSCC, HCC and CCC.
Time frame: 30 Months
Plan to share: Undecided
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
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Esophageal Squamous Cell Carcinoma →