Barrett’s Oesophagus

Introduction

Barrett’s oesophagus refers to metaplasia of the oesophageal epithelial lining, whereby normal stratified squamous epithelium is replaced by simple columnar epithelium.

The prevalence ranges from 0.5-2% in the Western world. Around 10% of patients with gastro-oesophageal reflux disease (GORD) will have already developed Barrett’s oesophagus by the time they seek medical attention.

In this article, we shall look at the causes, clinical features and management of Barrett’s oesophagus.

Pathophysiology

Metaplasia is the abnormal reversible change of one cell type to another. In Barrett’s oesophagus, the normal stratified squamous layer of the oesophagus is replaced by simple columnar (glandular) epithelium (as present in the stomach).

The vast majority of cases are caused by chronic gastro-oesophageal reflux disease. The epithelium of the oesophagus becomes damaged by the reflux of gastric contents, resulting in a metaplastic transformation. This in turn increases the risk of developing dysplastic and neoplastic changes.

The distal oesophagus is most commonly affected. Diagnosis relies on biopsy, demonstrating the presence of simple columnar epithelium within the oesophagus.

By Nephron (Own work) [CC BY-SA 3.0], via Wikimedia Commons

Figure 1 – Barrett’s oesophagus at the GOJ, showing gastric acinar metaplasia (on the left) and oesophageal stratified squamous epithelium (on the right)

Risk Factors

The risk factors for developing Barrett’s oesophagus include Caucasian ethnicity, male gender, age >50yrs, smoking, obesity, and the presence of hiatus hernia.

Investigations

Barrett’s oesophagus is a histological diagnosis. Patients who undergo upper GI endoscopy for chronic or resistant GORD (or to exclude malignancy) should have a biopsy taken of the oesophageal epithelium and sent for histological analysis.

At endoscopy, the oesophagus appears red and velvety in cases of Barrett’s oesophagus (FIg. 2), with some preserved pale squamous islands.

Samir धर्म, via Wikimedia Commons

Figure 2 – The endoscopic appearance of Barrett’s oesophagus

Management

All patients with Barrett’s oesophagus should be commenced on a proton-pump inhibitor (typically starting at a high dose and twice daily).

Any medication that impacts the stomach protective barriers (such as NSAIDs) should be stopped. In addition, the patient should be provided with lifestyle advice, including reduced alcohol intake and weight loss.

The major risk of Barrett’s oesophagus is progression to adenocarcinoma. Therefore, all patients with confirmed Barrett’s oesophagus must undergo regular endoscopy (Table 1).  The frequency of this depends on the degree of dysplasia identified by the biopsies (if any).

Table 1 – Example timetable of surveillance endoscopy needed for Barrett’s oesophagus

Prognosis

High grade dysplasia has a high risk of progressing to cancer so should be resected with endoscopic mucosal resection (EMR) or endoscopic submucosal dissection (ESD).

Adenocarcinomas detected on routine screening for Barrett’s oesophagus are typically early-stage lesions and have a better prognosis than those discovered outside of any screening program.