Figure 1  .

Barrett's cytokeratin 7 and 20 (CK7/CK20) pattern in biopsy specimens from the Z line with incomplete (A) and complete (B) intestinal metaplasia. (A) Diffuse strong CK7 staining of surface epithelium (arrow) and deep glands (arrowheads). Immunoperoxidase with nuclear counterstain by Mayer's haematoxylin (original magnification ×200). (B) Band-like CK20 staining of superficial epithelium (arrow). Absent immunoreactivity of deep glands (arrowheads). Immunoperoxidase with nuclear counterstain by Mayer's haematoxylin (original magnification ×200).