[Cytokeratin immunoreactivity patterns in the diagnosis of Barrett's esophagus]

To compare the expression patterns of cytokeratin 7 (CK7) and CK20 in the Barrett's esophagus and gastric cardia intestinal metaplasia.

Endoscopic biopsy specimens from 19 patients with long segment Barrett's esophagus, 36 with short segment Barrett's esophagus, and 20 with histological evidence of gastric cardia intestinal metaplasia were immunostained for CK7 and CK20. The immunohistochemical data were analyzed in relation with the clinicopathological data of the patients including age, hiatal hernia, and Helicobacter pylori status.

The Barrett's pattern of CK7/20 expressions was found in all the 19 patients with long segment Barrett's esophagus, in 31 of the 36 (82%) patients with short segment Barrett's esophagus, and in 2 of the 20 (10%) patients with gastric cardia intestinal metaplasia. Patients with short segment Barrett's esophagus who had a Barrett's CK7/20 pattern showed similar clinicopathological findings to those with long segment Barrett's esophagus, while in cases of short segment Barrett's esophagus where no Barrett's CK7/20 pattern was found, the clinicopathological features were similar to those of gastric cardia intestinal metaplasia cases.

A Barrett's CK7/20 expression pattern is an objective marker of Barrett's mucosa. CK7 and CK20 reactivity patterns in routine endoscopic biopsy samples can reliably identify the location of intestinal metaplasia in the esophagus and stomach.