The Colorectal Breath Analysis (COBRA) Study

Imperial College London

Status: Completed

Conditions: Colorectal Adenocarcinoma; Colorectal Polyps; Colorectal Cancer

Treatments: Diagnostic Test: Breath sample

Study type: Observational

Funder types: Other

Identifiers

NCT03699163

17SM3783

Details and patient eligibility

About

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.

Full 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.

Enrollment: 1,855 patients

Sex: All

Ages: 18 to 90 years old

Volunteers: No Healthy Volunteers

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

Exclusion criteria

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

Trial design

1,855 participants in 2 patient groups

Non cancer control patients

Description:

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. Those without a finding of colorectal adenocarcinoma will go into this group.

Treatment:

Diagnostic Test: Breath sample

Colorectal cancer patients

Description:

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. 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. Those with a finding of colorectal adenocarcinoma will go into this group.

Treatment:

Diagnostic Test: Breath sample