Clinical trial NCT02407392: "Using Dilute Vinegar to Find Changes in Cells During Endoscopy for Patients With Barrett's Oesophagus" (The ABBA Study)
Official title: Acetic Acid Guided Biopsies in Barrett's Surveillance for Neoplasia Detection Versus Non-targeted Biopsies (Seattle Protocol): A Feasibility Study for a Randomised Tandem Endoscopy Trial. The ABBA Study.
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Barrett Esophagus
Lead sponsor: Portsmouth Hospitals NHS Trust
Sponsor class: OTHER_GOV
Collaborators: name: University Hospitals, Leicester
name: University of Portsmouth
name: Brighton and Sussex University Hospitals NHS Trust
name: Western Sussex Hospitals NHS Trust
name: Royal Bournemouth and Christchurch Hospitals NHS Foundation Trust
name: Gloucestershire Hospitals NHS Foundation Trust
First posted: 2015-04-03
Enrollment: 200
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: CROSSOVER
Primary purpose: DIAGNOSTIC

Brief summary: Problem statement Barrett's oesophagus is a pre-cancerous condition affecting 375,000 people in the U.K. There is a 0.5-3% yearly risk of progressing to oesophageal cancer, from which only 5% of patients will survive for 5 years after diagnosis. Diagnosing the disease at the stage of dysplasia (pre-cancerous) and early cancer improves survival. This has led to the current surveillance strategy of gastroscopy with non-targeted mapping biopsies taken from the Barrett's oesophagus every two years. The large number of biopsies required is time consuming and expensive, yet dysplasia and cancerous tissue is still missed due to the non-targeted biopsy sampling strategy. Acetic acid has been used effectively in the early detection of cervical dysplasia and cancer, and has also been used with success in a high risk Barrett's population (patients with suspected dysplasia or previously treated dysplasia), but not been studied in the lower risk Barrett's surveillance population. A diagnostic study of non-targeted mapping biopsies (current practice) versus targeted biopsies (acetic acid) in a surveillance population is needed before widespread adoption of this technique is possible.

Detailed description: This is a feasibility study to enable powering of a larger study. The investigators would assume a disease detection of 4.5% with acetic acid chromoendoscopy and 1.5% with protocol driven mapping biopsies. However, these assumptions are largely driven from a single centre cohort study and as such need clarification before they could be used for the purposes of powering a study. Based on the historical cohort studies and wide consultation within the British Society of Gastroenterology research committee and consultation with experts in the field, it is estimated that 200 patients would be reasonable for recruitment to enable the reproducibility and generalisability of this data to be established. The purpose of this study is not to produce statistically significant data in itself but to establish likely event rates and effect size to inform the power calculation for the definitive study.

Eligibility criteria: Inclusion Criteria:

1. Aged 18 years or above
2. Biopsy proven Barrett's metaplasia
3. At least 2cm of Barrett's metaplasia (C0 M2)
4. Willing and able to give informed consent

Exclusion Criteria:

1. Less than 2cm (C0 M2) of Barrett's metaplasia
2. Significant oesophagitis
3. Known or prior oesophageal cancer
4. Known or prior oesophageal dysplasia (indefinite for dysplasia CAN be included)
5. Previous endoscopic therapy
6. Known allergy to acetic acid
7. Previous inclusion in the study

Primary outcomes:
measure: Feasibility as assessed by the ratio of patients approached to recruited, percentage of patients who complete both endoscopies
timeFrame: 18 months
Secondary outcomes:
measure: Participant acceptability of trial design
timeFrame: 18 months
measure: Comparison of dysplasia rates as assessed by the number of biopsies in each endoscopy required to detect dysplasia
timeFrame: 18 months
measure: Feasibility of training in Acetic Acid technique
timeFrame: 18 months
measure: Clinician's acceptability of using Acetic Acid technique
timeFrame: 18 months
measure: Facilitators and barriers to recruitment
timeFrame: 18 months
measure: Number of adverse events
timeFrame: 18 months
Other outcomes:
Locations:
city: Portsmouth
country: United Kingdom
facility: Queen Alexandra Hospital
Study officials:
affiliation: Portsmouth Hospitals NHS Trust
name: Pradeep Bhandari, MBBS, MD
role: PRINCIPAL_INVESTIGATOR
References: