title: Pathophysiology of Barrett's esophagus-associated neoplasia: circumferential spatial predilection.
abstract: The prevalence rates of Barrett's esophagus (BE) and esophageal adenocarcinoma (EAC) arising from BE show striking geographic patterns as they are much more common in Western as compared with Asian countries. However, recent epidemiological studies indicate that the number of patients with BE and EAC are gradually increasing in Asia including Japan, corresponding to the increase in prevalence of gastroesophageal reflux disease (GERD). Because the prognosis of patients with advanced-stage EAC remains poor, early detection of neoplastic lesion in those with BE has led to recent interest in effective treatment. Several promising studies have revealed that early neoplasia in BE is mainly located in the right anterior wall of the distal esophagus. Interestingly, this endoscopic characteristic has been found in both Western and Japanese populations. Potential pathophysiologic explanations underlying the circumferential distribution of neoplasia in BE include a nonuniform asymmetric distribution of esophageal acid exposure, with a tendency toward mucosal acid-related injury on the right side of the esophageal wall in patients with GERD, and the functional structure of the lower esophageal sphincter. Findings of the present study should improve lesion detection and aid in developing a target biopsy protocol for surveillance of BE.
authors: Department of Gastroenterology and Hepatology, Shimane University School of Medicine, Izumo, Japan.
authors: Norihisa
authors: N
authors: Ishimura
authors: Mayumi
authors: M
authors: Okada
authors: Hironobu
authors: H
authors: Mikami
authors: Eiko
authors: E
authors: Okimoto
authors: Naoki
authors: N
authors: Fukuda
authors: Goichi
authors: G
authors: Uno
authors: Masahito
authors: M
authors: Aimi
authors: Naoki
authors: N
authors: Oshima
authors: Shunji
authors: S
authors: Ishihara
authors: Yoshikazu
authors: Y
authors: Kinoshita
mesh_terms: D000230:Adenocarcinoma / Q000209:etiology / Q000473:pathology*; D001471:Barrett Esophagus / Q000150:complications / Q000473:pathology*; D004938:Esophageal Neoplasms / Q000209:etiology / Q000473:pathology*; D004945:Esophagoscopy; D004947:Esophagus / Q000473:pathology*; D006801:Humans