What is the role of cytokeratins in Barrett/cardia differentiation?
The importance of distinguishing between Barrett metaplasia and intestinal metaplasia of the gastric cardia is now accepted, and the management of each entity is quite different. Patients with Barrett metaplasia are enrolled in surveillance programs, consisting of periodic endoscopy and biopsy, because of the known risk of developing adenocarcinoma of the esophagus. Patients with intestinal metaplasia of the gastric cardia, however, are not currently enrolled in such programs, because this condition carries a low risk of developing adenocarcinoma of the gastric cardia. The distinction between both conditions by morphologic examination of routine histologic sections of endoscopic biopsies is extremely difficult if at all possible. A group of investigators proposed the use of immunostains for cytokeratin (CK) 7 and CK20 to overcome such difficulty. They concluded that the Barrett CK7/CK20 pattern was a highly sensitive and specific marker for Barrett metaplasia. Their observations, however, were not confirmed by other investigators. However, because it may be associated with premalignant lesions elsewhere in the gastric mucosa, we propose that intestinal metaplasia of the gastric cardia may have the same clinical implication as Barrett metaplasia.