A 54-year-old man comes to the clinic because of 4 months of progressive difficulty swallowing solid foods. He has a 30 pack-year smoking history and drinks alcohol daily. Upper endoscopy shows a friable distal esophageal mass, and biopsy is obtained from adjacent uninvolved mucosa. The normal mucosa from this region lacks keratin, is designed to resist abrasion from swallowed food, and contains multiple cell layers. Which of the following epithelial types normally lines this structure?
- A)Keratinized stratified squamous epithelium
- B)Transitional epithelium
- C)Nonkeratinized stratified squamous epitheliumGABARITO
- D)Simple columnar epithelium with goblet cells
- E)Pseudostratified ciliated columnar epithelium
Explicação
The normal esophagus is lined by nonkeratinized stratified squamous epithelium, which protects against mechanical abrasion from swallowed food. The clue is the biopsy from adjacent uninvolved esophageal mucosa in a patient with dysphagia, where the question as... Ver explicação completa e trilha adaptativa →