[Methylene blue chromoendoscopy for Barrett's esophagus diagnosis]

Barrett's esophagus is a condition in which the normal stratified squamous epithelium of the esophagus is replaced by specialized intestinal metaplasia, that carries an increased risk for the development of adenocarcinoma of the esophagus. Dysplasia and initial stage carcinoma generally precede this neoplasm; the increased risk has led to attempts at early detection of these lesions through periodic upper endoscopy and biopsies. The continued rise in the incidence of adenocarcinoma of the esophagus has fueled resurgent interest in the use of a variety of endoscopic techniques, like methylene blue chromoendoscopy, to improve the diagnosis of Barrett's esophagus and associated complications.

To determine if methylene blue chromoendoscopy directed biopsies offer advantage over the conventional technique in the detection of Barrett's esophagus.

Forty-five patients with previous diagnosis of Barrett's esophagus were enrolled in this study; all of them underwent upper endoscopy with random biopsies and upper endoscopy with methylene-blue directed biopsies within 4 weeks, in the period between April and October, 2002.

Results of histologic examination of random biopsies and those of methylene blue directed biopsies were compared. Sensitivity, specificity, positive and negative predictive values were 62,5%, 15,4%, 57,7% and 18,2%, respectively. No significant differences were found in the total number of biopsy specimens. Differences were found in the total amount of time spent during each procedure (chromoendoscopy x conventional technique), with chromoendoscopy being significantly longer.

We concluded that methylene blue chromoendoscopy offered no advantage over the conventional method in the diagnosis of Barrett's esophagus.