Barrett EsophagusBarrett esophagus is a complication ofchronic GERD ( 5-15%) that is characterized byintestinal metaplasia withinthe esophageal squamous mucosa.• Barrett esophagus is defined as the replacementof the normal distal stratified squamous mucosaby metaplastic columnar epithelium containinggoblet cells.
Epidemiology• The incidence of Barrett esophagus is rising,and it is estimated to occur in as many as 10%of individuals with symptomatic GERD.• Barrett esophagus is most common in white(Caucasian) males and it typically presents between40 and 60 years of age.• The greatest concern in Barrett esophagus isthat it confers an increased risk ofesophageal adenocarcinoma.
A pre-malignant conditionMolecular studies suggest thatBarrett epithelium may be moresimilar to adenocarcinoma thanto normal esophageal epithelium,consistent with the view thatBarrett esophagus is a pre-malignant condition.
Epithelial dysplasiaEpithelial dysplasia, considered to bea pre-invasive lesion, is detected in0.2% to 2.0% of persons withBarrett esophagus each year and isassociated with prolongedsymptoms and increased patientage
90%Although the vast majority of esophagealadenocarcinomas are associated with Barrettesophagus,it is important to remember that most(90%) individuals with Barrettesophagus do not develop esophagealtumors.
Red PatchesBarrett esophagus can be recognized as one orseveral tongues or patches of red, velvetymucosa extending upward from thegastroesophageal junction.
AlternatesMetaplastic mucosaalternates with residualsmooth, pale squamous(esophageal) mucosa andinterfaces with light-brown columnar(gastric) mucosa distally.
Long segment & Short segmentHigh-resolution endoscopes have increased thesensitivity of Barrett esophagus detection. Thishas led to subclassification of Barrett esophagusas long segment, in which 3 cm or more ofesophagus is involved, or short segment, inwhich less than 3 cm is involved. It is not yetclear if the risk of dysplasia in short segmentdisease is less than in long segment Barrettesophagus.
Short Segment Barrett’sIrregular z-line above hiatal herniaCourtesy of Dr. C. Mel WilcoxCourtesy of Dr. C. Mel Wilcox
What we want to prevent --Cancer Arising in Barrett’sCourtesy of Dr. C. Mel WilcoxCourtesy of Dr. C. Mel Wilcox
Diagnosis• Diagnosis of Barrett esophagus requires bothendoscopic evidence of abnormal mucosa abovethe gastroesophageal junction and histologicallydocumented intestinal metaplasia.
Goblet cells• Goblet cells, which have distinct mucous vacuolesthat stain pale blue by H&E and impart the shapeof a wine goblet to the remainingcytoplasm, define intestinal metaplasia and arenecessary for diagnosis ofBarrett esophagus
Intestinal metaplasia• The requirement for intestinal metaplasiareflects the fact that this feature correlateswith neoplastic risk.• Foveolar mucus cells, which do not havedistinct mucous vacuoles are insufficient fordiagnosis.
Role of EndoscopyThe requirement for an endoscopic abnormalityhelps to prevent misdiagnosisif metaplastic goblet cells within the cardia areincluded in the biopsy.
Dysplasia• When dysplasia is present, it is classified as lowgrade or high grade. Increased epithelialproliferation, often with atypical mitoses,nuclear hyperchromasia and stratification,irregularly clumped chromatin, increasednuclear-to-cytoplasmic ratio, and a failure ofepithelial cells to mature as they migrate to theesophageal surface are present in both gradesof dysplasia.
Dysplasia cont.• Gland architecture is frequently abnormaland is characterized by budding, irregularshapes, and cellular crowding.• High-grade dysplasia exhibits more severecytologic and architectural changes.Intramucosal carcinoma ischaracterized by invasion ofneoplastic epithelial cells into thelamina propria.
Barrett esophagus. A, Normal gastroesophageal junction. B, Barrettesophagus. Note the small islands of paler squamous mucosa within the Barrett mucosa. C,Histologic appearance of the gastroesophageal junction in Barrett esophagus. Note thetransition between esophageal squamous mucosa (left) and Barrett metaplasia, withabundant metaplastic goblet cells (right).
Clinical Features.• Barrett esophagus can only be identified thoroughendoscopy and biopsy,which are usually prompted by GERD symptoms(dysphagia, heartburn,regurgitation of sour-tastinggastric contents & attacks ofsevere chest pain).
TreatmentSurgical resection, or esophagectomy,Photodynamic therapy,Laser ablation, andEndoscopic mucosectomy.
Future HopeManagement of esophageal dysplasia is evolving,and it is hoped that improved molecularunderstanding of neoplastic progressionmay allow development of chemopreventiveapproaches that reduce incidence ofesophageal adenocarcinoma.
Points to Remember1. In Barretts esophagus, the tissue lining the esophagus isreplaced by tissue that is similar to the lining of the intestine.2. Barretts esophagus is associated with gastroesophageal refluxdisease (GERD).3. Improvement in GERD symptoms with acid-reducing drugs maydecrease the risk of developing Barretts esophagus.4. Barretts esophagus is diagnosed through an uppergastrointestinal endoscopy and biopsies.5. People who have Barretts esophagus should have periodicsurveillance endoscopies and biopsies.6. Endoscopic treatments are used to destroy Barretts tissue,which will hopefully be replaced with normal esophageal tissue.7. Removal of most of the esophagus is recommended if a personwith Barretts esophagus is found to have severe dysplasia orcancer and can tolerate a surgical procedure.