Heterotopic Gastric Mucosa of the Esophagus: Literature-Review and Proposal of a Clinicopathologic Classification

Abstract

The prevalence of heterotopic gastric mucosa (HGM) in the cervical esophagus is frequently underestimated. Tiny microscopic foci have to be distinguished from a macroscopically visible patch, also called "inlet patch." Symptoms as well as morphologic changes associated with HGM are regarded as a result of the damaging effect of acid, produced by parietal cells in the mostly fundic type of HGM. We herein review the literature and propose a new clinicopathologic classification of esophageal HGM: Most of the carriers of esophageal HGM are asymptomatic (HGM I). Some individuals with HGM in the esophagus complain of dysphagia, odynophagia, or "extraesophageal manifestations" (hoarseness and coughing), without further morphologic findings (HGM II). Still fewer patients are symptomatic due to morphologic changes, i.e., esophageal strictures, webs, or esophagotracheal fistula (HGM III). Malignant transformation via dysplasia (intraepithelial neoplasia, HGM IV) to cervical esophageal adenocarcinoma (HGM V) is exceedingly rare (only 24 reported cases). In contrast to Barrett's esophagus, HGM should not be regarded as a precancerous lesion. Symptoms are more likely to occur in patients with inlet patch, whereas malignant transformation and adenocarcinogenesis can also occur in microscopic HGM foci. Asymptomatic HGM requires neither specific therapy nor endoscopic surveillance. Only in symptomatic cases treatment, i.e., dilatation for (benign) strictures or acid suppression for reflux symptoms, can be recommended. Patients with low-grade dysplasia in HGM might be candidates for surveillance strategies, whereas in cases of high-grade dysplasia and invasive adenocarcinoma oncological treatment strategies must be employed.

Olgu sunumu: Servikal özofagusta dev inlet patch

“…Özofagiyal HGM, embriyolojik dönemde özofageal epitelizasyonun eksik kalmas› sonras›nda geliflen konjenital anomalidir (7). Gestasyonel yaflam›n 10. haftas›nda özofagus tek katl› kolumnar epitel ile döflelidir.…”

Long segments of columnar-lined lower esophagus are not always metaplastic

“…Less frequently, HGM shows a "transitional" cell type characterized by mucous glands without chief cells and with only a few parietal cells, called oxyntocardiac (17). There are scarce references of the presence of pure cardiac epithelium (18), and references of the presence of intestinal metaplasia are extremely rare (6).…”

“…In a literature review, von Rahden et al (6) verified that most of the mucosa of HGM is uniformly the oxyntic type and is characterized by glands with chief and parietal cells. Less frequently, HGM shows a "transitional" cell type characterized by mucous glands without chief cells and with only a few parietal cells, called oxyntocardiac (17).…”

“…HGM is thought to have a congenital origin resulting from the incomplete squamous epithelialization of the esophagus during embryologic development (4,5). Histologically, most HGM cases consist of oxyntic mucosa with mucus-secreting columnar cells, chief cells, and parietal cells (4,6). Although a recent published review found 44 cases of adenocarcinoma arising in HGM (7), it is not considered a pre-malignant condition.…”

“…Reports of its occurrence in the lower esophagus are uncommon and always describe HGM as small islands (6). Chandrasoma (9) recently stated that it is hard to find in the literature any significant reference to "islets of gastric mucosa in the lower esophagus" after 1950 Barrett's paper on Chronic ulcer of the esophagus and "esophagitis" (10).…”