CDX2 immunohistochemical marker for Barett's esophagus: useful or useless? CDX2 in Barett's esophagus

The diagnosis of Barrett's esophagus (BE) is challenging in the absence of goblet cells (GC). Immunohistochemistry (IHC) may be useful to highlight intestinal differentiation in samples lacking GC. In this study, we aimed to describe the IHC expression of CDX2 in columnar cells of BE and to assess its diagnostic and prognostic utility. This retrospective study, conducted from 2010-2015,included cases suspicious of BE examined in our pathology department. Only cases positive for GC (Alcian Blue positive) were diagnosed as BE. An automated IHC analysis was performed using CDX2. Nuclear CDX2 expression was evaluated in IM zones(goblet cells) and adjacent tissue (columnar cells). OF 39 cases, the diagnosis of BE was confirmed in 34 cases. The mean age of patients was 53 years with a male-to-female ratio of 2.4.Endoscopically, 20 patients had short-segment BE (59%), 8 had ultra-short-segment BE (23%) and 6 had long-segment BE (18%).Histologically, an associated adenocarcinoma was found in two cases. In non-neoplastic BE, nuclear CDX2 expression was observed in both GC (88.2%) and adjacent columnar cells(26.5%). A statistically significant association was found between CDX2 expression and GC (p < 0.005).Both adenocarcinoma cases were CDX2-positive in BE areas but CDX2-negative in tumor foci. CDX2 has a high sensitivity and specificity for IM and its expression is associated with GC. However, its low expression in adjacent columnar cells limits its benefit in BE specimens lacking GC.