The Colorectal Breath Analysis (COBRA) Study

Completed

• Conditions: Colorectal Polyps; Colorectal Adenocarcinoma; Colorectal Cancer
• Interventions: Diagnostic Test: Breath sample

• Registration Number: NCT03699163
• Lead Sponsor: Imperial College London

Brief Summary

This study aims to determine whether a breath test could be used for early detection of colorectal cancer and colorectal polyps.

Patients who are attending for a planned colonoscopy or who are scheduled to undergo elective resection of histologically confirmed colorectal cancer (adenocarcinoma) will be approached to provide a breath sample.

Multi platform mass spectrometry analysis will be performed to establish volatile biomarkers that can discriminate between colorectal cancer, benign colorectal disease (e.g. polyps) and healthy controls.

Detailed Description

Colorectal cancer is the 2nd most common cause of cancer death in the UK where survival rates are among the lowest in Europe. If diagnosed early survival may exceed 90%.

The proposed breath test is a non-invasive investigation that can detect the presence of volatile organic compounds (VOCs) in breath and their relative abundance in disease states including colorectal cancer. This test has potential to be used in a primary care setting to identify patients at high risk of colorectal cancer, supporting earlier referral for definitive investigation. A negative test may provide reassurance to patients and prevent unnecessary tests in this group. The test could also have an application for colorectal cancer screening.

In this study the investigators will determine the diagnostic accuracy of an exhaled breath test for the detection of colorectal adenocarcinoma and colonic polyps. To determine the accuracy of the breath test a multicentre cross-sectional study will be conducted to analyse single breath samples from patients attending hospital for planned colonoscopy or elective resection of histologically confirmed colorectal cancer. The target for the study is 1463 patients.

Breath collection will be conducted using a previously validated method. Samples of breath (500ml) collected using a CE-marked handheld ReCIVA sampling device (Owlstone Medical Ltd., Cambridge, UK) during a period of tidal breathing (approximately 5minutes) will be absorbed onto thermal desorption tubes (Markes International, Llantrisant, UK). All patients will have received bowel preparation and will be fasted for a minimum of 6 hours prior to the breath sample. Breath samples collected within thermal desorption tubes will be transferred to a central laboratory for analysis by gas chromatography mass spectrometry (GC-MS) and proton transfer reaction time of flight mass spectrometry (PTR-ToF-MS). Raw data files will be extracted and analysed in accordance with established protocols. Quality assurance measures will be formally assessed at each stage of sample handling.

Basic Information
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Recruitment & Eligibility
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Study & Design
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Trial Locations

Study Timeline

• Study Start: 2017-06-03
• Study First Submitted: 2018-10-03
• Study First Submitted QC: 2018-10-04
• Study First Posted: 2018-10-09
• Primary Completion: 2020-07-01
• Study Completion: 2022-04-01
• Results First Submitted: 2023-03-27
• Status Verified: 2024-09
• Results First Submitted QC: 2024-09-24
• Last Update Submitted: 2024-09-24
• Results First Posted: 2024-11-21
• Last Update Posted: 2024-11-21

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 1855

Inclusion Criteria

• ≥18 years and ≤90 years of age
• Undergoing planned colonoscopy or elective resection of histologically confirmed colorectal adenocarcinoma
• Fasted >6 hours
• Able to provide informed written consent

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Exclusion Criteria

• Any patient <18 years or >90 years of age.
• Lacks capacity or is unable to provide informed written consent.

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Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Arm && Interventions

Group	Intervention	Description
Endoscopy patients	Breath sample	Patients who are attending hospital for a colonoscopy as part of their routine clinical care, or as part of the Bowel Cancer Screening Programme, will be asked to give a sample of their breath prior to the procedure.
Colorectal cancer patients	Breath sample	Patients who have known pre-diagnosed colorectal cancer (adenocarcinoma) attending hospital as part of their clinical care will be asked to give a breath sample prior to their cancer operation.

Primary Outcome Measures

Name	Time	Method
Determine the Diagnostic Accuracy of the Proposed Breath Test for Detection of Colorectal Cancer in All Patients	30 minutes	Diagnostic accuracy will be measured by calculating the sensitivity and specificity of the test for detection of colorectal cancer, as diagnosed on colonoscopy, using 14 specific VOCs plus BMI as prediction variables.
Determine the Diagnostic Accuracy of Using VOCs Present in Breath for the Detection of Colorectal Cancer in Symptomatic Patients	30 minutes	Diagnostic accuracy will be measured by calculating the sensitivity and specificity of the test for detection of colorectal cancer, as diagnosed on colonoscopy, using 14 specific VOCs plus BMI as prediction variables.

Trial Locations

Locations (8)

Chelsea and Westminster Hospital; 🇬🇧 London, United Kingdom

St Mary's Hospital; 🇬🇧 London, United Kingdom

West Middlesex Hospital; 🇬🇧 London, United Kingdom

Homerton Hospital; 🇬🇧 London, United Kingdom

St Mark's Hospital; 🇬🇧 London, United Kingdom

St George's Hospital; 🇬🇧 London, United Kingdom

Royal Marsden Hospital; 🇬🇧 London, United Kingdom

Charing Cross Hospital; 🇬🇧 London, United Kingdom