2. INTRODUCTION:
Barrett esophagus sometimes called Barrett
syndrome or columnar epithelium lined lower
oesophagus (CELLO), refers to an abnormal change
(metaplasia) in the cells of the lower portion of
the esophagus.
When the normal squamous epithelium lining of the
esophagus is replaced by goblet cells(cells usually found
lower in the gastrointestinal tract), Barrett's esophagus is
diagnosed.
The medical significance of Barrett esophagus is its strong
association with esophageal adenocarcinoma, a particularly
lethal cancer.
3. CAUSES:
An adaptation to chronic acid exposure
from reflux esophagitis
Gastroesophageal reflux disease GERD
4. SIGNS AND SYMPTOMS:
The change from normal to premalignant cells that indicate Barrett
esophagus does not cause any particular symptoms.
Barrett esophagus, however, is associated with the following symptoms:
frequent and longstanding heartburn
trouble swallowing (dysphagia)
vomiting blood (hematemesis)
pain under the breastbone where the esophagus meets the stomach
unintentional weight loss because eating is painful
The risk of developing Barrett esophagus is increased by central
obesity (vs. peripheral obesity).
5. MECHANISM
Barrett esophagus occurs due to chronic inflammation.
The principal cause of the chronic inflammation is GERD.
In this disease, acidic stomach, bile, small intestine and
pancreatic contents cause damage to the cells of the lower
esophagus.
Recently, it was shown that bile acids are able to induce
intestinal differentiation, in gastroesophageal junction cells,
through inhibition of the Epidermal growth factor receptor
(EGFR) receptor and the protein kinase enzyme Akt.
6. DIAGNOSIS:
Diagnosis of Barrett esophagus requires endoscopy (more
specifically,esophagogastroduodenoscopy, a procedure in which a
fibre optic cable is inserted through the mouth to examine the
esophagus, stomach, and duodenum) and biopsy.
Barrett esophagus is marked by the presence of columnar
epithelia in the lower esophagus, replacing the normal squamous
cell epithelium—an example of metaplasia
The cells of Barrett esophagus, after biopsy, are classified into four
general categories:
1. non-dysplastic
2. low-grade dysplasia
3. high-grade dysplasia
4. frank carcinoma
5. High-grade dysplasia
7. MANAGEMENT:
Treatment options for high-grade dysplasia include:
- surgical removal of the esophagus (esophagectomy)
- endoscopic treatments such as endoscopic mucosal resection or
radiofrequency ablation (destruction).
Proton pump inhibitor drugs have not yet been proven to prevent
esophageal cancer.
Laser treatment is used in severe dysplasia, while overt malignancy may
require surgery, radiation therapy, or systemic chemotherapy.
Endoscopic mucosal resection (EMR) has also been evaluated as a
management technique. Additionally an operation known as a Nissen
fundoplication can reduce the reflux of acid from the stomach into the
esophagus.
In a variety of studies, non-steroidal anti-inflammatory drugs (NSAIDS),
like aspirin, have shown evidence of preventing esophageal cancer in
Barrett esophagus patients.