Scanning electron microscopy of Barrett's epithelium and its correlation with light microscopy and mucin stains.

The surface epithelial cells of Barrett's esophagus were characterized using quantitative scanning electron microscopy and light microscopy with mucin histochemical stains. Fifty-one biopsy specimens of Barrett's esophagus from 15 patients and 31 control specimens of the stomach and intestines from 9 patients were examined. Three distinct surface cell types, in addition to the goblet cell, were recognized in Barrett's epithelium: the gastric-like cell in 31% of specimens, which was similar to the normal gastric surface cell by quantitative scanning electron microscopy; the intestinal-like cell in 41%, which was most similar to the normal small intestinal surface cell; and the variant cell in 80%, which had a range of surface features. By light microscopy, all specimens with variant and intestinal-like cells were classified as specialized columnar epithelium. The surface mucous cells in Barrett's epithelium displayed a variety of mucin staining patterns with acid nonsulfated (small intestinal-like) mucin present in 90% of specimens and acid sulfated (colonic-like) mucin in 43% of specimens. Quantitative scanning electron microscopy and mucin histochemical stains reveal a striking cellular heterogeneity not apparent by routine light microscopy.