Immunohistochemical/histochemical double staining method in the study of columnar metaplasia of the oesophagus

Intestinal metaplasia in Barrett’s oesopha- gus (BO) represents an important risk factor for oesophageal adenocarcinoma. Instead, few and controversial data are reported about the progression risk of columnar-lined oesophagus without intestinal metaplasia (CLO), posing an issue about its clinical management. The aim was to evaluate if some immunophenotyp- ic changes were present in CLO independently of the presence of the goblet cells. We studied a series of oesophageal biopsies from patients with endoscopic finding of columnar metapla- sia, by performing some immunohistochemical stainings (CK7, p53, AuroraA) combined with histochemistry (Alcian-blue and Alcian/PAS), with the aim of simultaneously assess the his- tochemical features in cells that shows an aber- rant expression of such antigens. We evidenced a cytoplasmic expression of CK7 and a nuclear expression of Aurora A and p53, both in goblet cells of BO and in non-goblet cells of CLO, some of which showing mild dysplasia. These find- ings suggest that some immunophenotypic changes are present in CLO and they can pre- cede the appearance of the goblet cells or can be present independently of them, confirming the conception of BO as the condition charac- terized by any extention of columnar epitheli- um. This is the first study in which a combined immunohistochemical/histochemical method has been applied to Barrett pathology.