The Usefulness of Magnifying Chromoendoscopy with Methylene Blue in the Detection of Specialized Intestinal Metaplasia and Dysplasia in Barrett’s Esophagus — a Preliminary Report

Background: Barrett’s esophagus appears in relation with gastroesophageal reflux disease, which damages the normal squamous mucosa; the injury heals through a metaplastic process in which columnar cells replace squamous ones. The specialized intestinal metaplasia has a malignant potential, but the diagnosis is often difficult in conventional endoscopy.
Aim: Our purpose was to evaluate the results of magnifying chromoendoscopy using methylene blue in the diagnosis of specialized intestinal metaplasia and dysplasia in Barrett’s esophagus.
Methods: Nine patients with proven or suspected Barrett’s esophagus in conventional endoscopy underwent magnified chromoendoscopy with methylene blue for confirming and/or monitoring the intestinal metaplasia or for detecting dysplasia. Biopsies were taken from sites coloured with methylene blue and from regions with particular patterns according to Endo’s classification.
Results: Specialized intestinal metaplasia was reported in 16 out of 29 biopsies; one biopsy proved low grade dysplasia and two samples showed indefinite for dysplasia. The sensitivity and specificity of methylene blue staining in detection of specialized intestinal metaplasia were 87% and 66% respectively (p=0.005). Taking into consideration Endo’s classification, tubular and villous patterns had a significant correlation with SIM detection (p=0.0004) with a sensitivity and a specificity of 66% and 100%.
Conclusions: Magnifying chromoendoscopy with methylene blue allows targeted biopsies for SIM and dysplasia detection; it also allows the selection of the site of the biopsy according to pitpattern.