Question

Barrett's oesophagus is characterised by :

• A. \( \text{Squamous metaplasia} \)
• B. \( \text{Columnar metaplasia} \)
• C. \( \text{Mesenchymal metaplasia} \)
• D. \( \text{Atypical hyperplasia} \)

Hint:

\textbf{Pathology: Barrett's Oesophagus.} Remember that Barrett's oesophagus involves the replacement of the normal squamous lining of the oesophagus with columnar epithelium, a process known as metaplasia, in response to chronic acid reflux. This metaplastic change is a risk factor for oesophageal adenocarcinoma.

Answer 1

The Correct Option is B

Barrett's oesophagus is a condition in which the normal stratified squamous epithelium lining the oesophagus is replaced by metaplastic columnar epithelium, often containing goblet cells, which are usually found in the intestine. This change is typically a result of chronic gastroesophageal reflux disease (GERD). The columnar metaplasia is considered a premalignant condition because it increases the risk of developing oesophageal adenocarcinoma. Let's briefly look at why the other options are incorrect: Squamous metaplasia: This is the replacement of one type of squamous epithelium by another type of squamous epithelium. It is not characteristic of Barrett's oesophagus. Mesenchymal metaplasia: This involves the transformation of one type of mesenchymal tissue into another (e.g., cartilage to bone). It is not relevant to the epithelial lining of the oesophagus in Barrett's oesophagus. Atypical hyperplasia: Hyperplasia is an increase in the number of cells in a tissue or organ. Atypical hyperplasia refers to an increase in cells that exhibit abnormal features (e.g., size, shape, organization). While dysplasia (disordered cellular growth) can occur in Barrett's oesophagus and is a further step towards malignancy, the defining characteristic of Barrett's oesophagus itself is the replacement of squamous epithelium with columnar epithelium (metaplasia). Therefore, Barrett's oesophagus is characterised by columnar metaplasia.