Variation in Barrett's Esophageal Wall Thickness: Is It Associated with Histology Or Segment Length?

Abstract

Background: Endosonography (EUS) provides detailed images that can be used to determine topographic esophageal wall characteristics in Barrett's esophagus (BE). Although increased esophageal wall thickness (EWT) has been reported in BE patients compared to controls, the relationship between EWT and degree of dysplasia is not known. This information may be important in guiding endoscopic ablation therapy where treatment effects may be related to EWT. The aim of this study was to measure distal EWT by EUS in consecutive BE patients of varying histology and segment length. Methods: Patients referred for evaluation of Barrett's dysplasia were studied with standard radial scanning EUS and compared to patients without esophageal disease undergoing EUS for other reasons (normal controls). The distal EWT was measured as the distance from the balloon-mucosal interface to the outermost hyperechoic line in the distal esophagus in patients without dysplasia (BE), low grade dysplasia (LGD), high grade dysplasia (HGD) and carcinoma in situ (CIS). Areas of endoscopically obvious nodularity or tumor were excluded from analysis. All BE patients were using twice daily proton pump inhibitor medication and no patients had endoscopic evidence of esophagitis. Results: Since 2004, 68 patients with BE (4 BE, 14 LGD, 46 HGD, 4 CIS) were studied (58 men, mean age 67 years, mean BE segment length 5 cm, range 1-20 cm) along with 53 normal controls (18 men, mean age 60 years). The mean (standard deviation) of distal EWT was 2.4 mm (0.6 mm) for controls, 3.1 (0.7) mm for non dysplastic BE, 3.2 (0.7) mm for LGD, 3.4 (1.1) mm for HGD, and 3.9 (1.0) mm for CIS. Esophageal wall thickness was significantly greater in all histologic subgroups of Barrett's esophagus patients compared to normal controls (p < 0.001, t-test). Though a trend was observed for increasing distal esophageal wall thickness with greater degrees of dysplasia in BE, it did not reach statistical significance (p = 0.55, Kruskal Wallis test). Additionally, there was no evidence of association of esophageal wall thickness with BE segment length (Spearman's rank correlation, r = 0.06, p = 0.62). Conclusions: The thickness of the distal esophageal wall is greater in patients with Barrett's disease compared with normal control patients. However, there were no systematic differences in wall thickness among groups of patients with Barrett's disease based on histology, and no association with Barrett's segment length. These findings are particularly important for patients being evaluated for endoscopic ablation therapy with varying depths of necrosis.