RESUMEN
BACKGROUND: Immunohistochemical changes associated with development of cancer in Barrett's esophagus offer potential areas of intervention to prevent and manage esophageal cancer. AIMS: To assess the role of cyclooxygenase 2, caudal-type homeobox transcription factor 2 and cell division cycle 2/cyclin-dependent kinase 1 in the Barrett's metaplasia-dysplasia-adenocarcinoma sequence. PATIENTS AND METHODS: Specimens from 46 patients with Barrett's esophagus (39% without dysplasia, 33% with dysplasia and 28% with adenocarcinoma) were stained for cyclooxygenase 2, caudal-type homeobox transcription factor 2 and cell division cycle 2. RESULTS: Cyclooxygenase 2: No expression differences between groups were found, except for adenocarcinomas (p=0.04). Caudal-type homeobox transcription factor 2: Nuclear positivity decreased from Barrett's esophagus without dysplasia (71.6%), to Barrett's esophagus with low grade dysplasia (35.3%), to Barrett's esophagus with high grade dysplasia (17.14%); in adenocarcinoma these percentages were intermediate between high and low grade dysplasia (30.5%). Cell division cycle 2: Expression on deeper glandular structures was 40% in Barrett's esophagus without dysplasia, 55.47% in Barrett's esophagus with dysplasia, and 63.84% in adenocarcinoma, with no statistical differences between groups. Concerning cells of the superficial layer, Barrett's esophagus with low grade dysplasia expressed focal positivity (p=0.0001 vs. no dysplasia); Barrett's esophagus with high grade dysplasia displayed diffuse positivity (p=0.0001 vs. no dysplasia and low grade dysplasia). A diffuse positivity was found in Barrett's esophagus with adenocarcinoma (p=0.0001 vs. no dysplasia and low grade dysplasia). CONCLUSIONS: Further evaluation of cyclooxygenase 2, cell division cycle 2 and caudal-type homeobox transcription factor 2, in association with morphology, might help to improve the accuracy of diagnosis and be useful for the clinical-pathological assessment of patients with Barrett's esophagus.