Biomarker studies in reversed Barrett's esophagus

OBJECTIVE: The purpose of this study was to use biomarkers to assess far ca ncer risk in Barrett's esophagus patients with either squamous islands or c omplete reversal of their intestinal metaplasia to squamous epithelium. METHODS: The biomarkers included proliferation characteristic using Ki-67, p53 abnormalities using immunohistochemical methods with two antibodies, DO -1 and DO-7, and ornithine decarboxylase (ODC) activity. RESULTS: Eleven patients had complete reversal produced by a combination of acid suppression and thermal injury (multipolar electrocoagulation). Ki-67 staining was indistinguishable from that of normal squamous esophageal epi thelium, i.e., basal layer staining only. All 11 cases were negative for p5 3. ODC activity was low and in the range for normal squamous epithelium. Fo urteen patients had squamous islands (partial reversal) after prolonged pro ton pump inhibitor therapy. Multilayer Ki-67 staining occurred in nine case s (64%), and six (43%) had areas of positive p53 staining. CONCLUSIONS: Initial biomarker studies suggest that completely reversed squ amous epithelium is biologically similar to normal squamous epithelium and of low cancer risk. In contrast, partial reversal, manifest as squamous isl ands, is accompanied by biomarker abnormalities. (C) 1999 by Am. Cell. of G astroenterology.