Can we diagnose early Barrett's oesophagus?

OBJECTIVES: The definition of Barrett's oesophagus, has been of late, is stressed on the presence of specialised columnar epithelium with goblet cells and not on other metaplastic epithelia, which however could be the early, immature, undifferentiated cell types such as junctional and gastric types. Hence this study was carried out to find out the ways of detecting the early metaplastic cell forms before the goblet cells appear. METHODS: Among 134 cases of reflux oesophagitis selected in the prospective study of 7 years from January 1992 to December 1998, 31 biopsies were diagnosed as Barrett's oesophagus (BO). These were compared with 20 age matched control biopsies from gastro-oesophageal junction. They were studied morphologically, morphometrically and histochemically for acid, neutral and sulphomucins using alcian blue (AB), alcian blue-periodic acid Schiff (AB-PAS) and high iron diamine-alcin blue (HID-AB) stains. RESULTS: Twelve of the cases were of junctional type, 16 of specialised columnar intestinal metaplastic (IM) type (Type I = 0, Type II = 5, Type III = 11) and three showed a combination of both junctional and Type I IM. Mucins were a mixture of neutral mucin, sialomucin and sulphomucin while the control biopsies showed chiefly neutral mucin. Morphometrically, the epithelial cells in BO were taller (mean 28u in junctional types and 32u in IM) in comparison to the control (mean 24.5 u). CONCLUSION: When the classical specialised columnar epithelium (with goblet cells) in oesophagus is absent, presence of metaplastic junctional type of mucosa, may, for all probabilities be considered as the initial step towards transformation to the classical Barrett's mucosa. In such situations, it is essential to differentiate it from the normal gastro-oesophageal junctional epithelium and is possible with histochemical analysis of the biopsy material aided by morphometry, especially so when the level of biopsy is not indicated.