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378 seCtion iii Gastrointestinal ` gastrointestinal—PatHology Gastrointestinal ` gastrointestinal—PatHology

Barrett esophagus Specialized intestinal metaplasia A —replacement of nonkeratinized stratified squamous
epithelium with intestinal epithelium (nonciliated columnar with goblet cells [stained blue in B ])
A
in distal esophagus. Due to chronic gastroesophageal reflux disease (GERD). Associated with
 risk of esophageal adenocarcinoma.

Squamocolumnar
Esophagus
(epithelial) junction
B (SCJ or Z line)
Lower
esophageal
sphincter

Stomach

Esophageal cancer Typically presents with progressive dysphagia (first solids, then liquids) and weight loss. Aggressive
course due to lack of serosa in esophageal wall, allowing rapid extension. Poor prognosis due to
advanced disease at presentation.
CanCer Part oF esoPHagUs aFFeCteD risK FaCtors PreValenCe
Squamous cell Upper 2/3 Alcohol, hot liquids, caustic More common worldwide
carcinoma strictures, smoking, achalasia
Adenocarcinoma Lower 1/3 Chronic GERD, Barrett More common in America
esophagus, obesity, smoking,
achalasia

FAS1_2019_09-Gastrointestinal.indd 378 11/7/19 4:42 PM