Does CDX2 expression predict Barrett's metaplasia in oesophageal columnar epithelium without goblet cells?

Background: Intestinal metaplasia (Barrett's oesophagus), but not cardiac-type mucosa in columnar-lined oesophagus, is regarded as premalignant. As intestinal metaplasia and cardiac-type mucosa are endoscopically indiscernible, it is difficult to take targeted samples from columnar-lined oesophagus with consequently a risk of having undetected intestinal metaplasia. Aim: To investigate whether the intestinal markers CDX2, MUC2 and villin can predict the presence of undetected intestinal metaplasia in columnar-lined oesophagus. Methods: Presence of intestinal metaplasia or cardiac-type mucosa was identified in 122 biopsy sets of columnar-lined oesophagus from 61 patients, collected at two subsequent follow-up upper endoscopies. CDX2, MUC2 and villin expression were determined by immunohistochemistry. Results: All intestinal metaplasia samples (55) were positive for CDX2 and MUC2 and 32 of 55 for villin. CDX2 expression was detected in 23 of 67 (34%) samples with only cardiac-type mucosa. Detection of CDX2 in cardiac-type mucosa increased the likelihood of finding intestinal metaplasia in another biopsy set of columnar-lined oesophagus (odds ratio 3.5, 95% CI = 1.2-10, P = 0.02). MUC2 was positive in 13 of 23 (57%) of CDX2-positive cardiac-type mucosa samples, whereas villin was detected in seven of 23 (30%). Conclusions: CDX2 expression in cardiac-type mucosa might be able to predict the presence of undetected intestinal metaplasia in columnar-lined oesophagus, and thus may be a putative marker for the presence of intestinal metaplasia in the absence of goblet cells.