PWE-078 Magnification Endoscopy with I-Scan Imaging and Acetic Acid Chromoendoscopy in Barrett’s Oesophagus Improves Neoplasia Detection

Abstract

Introduction Barrett’s oesophagus (BE) is the pre-cursor for oesophageal adenocarcinoma. Endoscopic surveillance is performed in BE patients to detect dysplasia as an early treatment target. Current surveillance relies on random quadrantic biopsies every 1–2 cm through the BE with targeted biopsies for areas of suspicion. This strategy samples less than 5% of the BE mucosa. We present a novel endoscopic classification system utilising magnification chromo-endoscopy with i-Scan (PENTAX HOYA, Japan) image enhancement technology and acetic acid to improve dysplasia recognition in BE. Methods High definition (HD) video recordings of suspicious lesions were collected from patients with non-dysplastic (ND-BE) and dysplastic (D-BE) BE undergoing endoscopy at a high volume tertiary centre. Lesions were recorded with magnification endoscopy in all i-Scan modes both before and after application of 2% acetic acid (ACA) before sampling with biopsy forceps or endoscopic mucosal resection to confirm the histological diagnosis. Six expert endoscopists scored videos using a previously validated mucosal (M) and vascular (V) classification system. Normal mucosa was defined as regular circular or villous pits (M1) and abnormal mucosa defined as distorted or irregular pits or featureless mucosa (M2). Normal vascular pattern was defined as regular and uniform vessels (V1) and abnormal vascular pattern was defined as irregular, dilated corkscrew vessels (V2). Dysplasia was classified if the lesion was felt to be either M2 or V2. Results 63 lesions (36 D-BE, 27 ND-BE) were recorded (30 before ACA and 33 after ACA) for analysis. Experts’ average accuracy for dysplasia prediction was 67.8% pre ACA and 75.9% after ACA (p = 0.01). ACA improved the sensitivity of our novel classification system for neoplasia detection from 81% to 88% (p = 0.04). Interobserver Kappa values were 0.253 pre ACA and 0.369 after ACA. Conclusion Experts can diagnose D-BE in up to three-quarters of cases using i-Scan magnification endoscopy with acetic acid. ACA improves the sensitivity of diagnosing D-BE. The novel classification system for BE neoplasia has fair agreement between expert endoscopists. Disclosure of Interest None Declared