Barrett's esophagus is a condition in which the squamous mucosa that normally lines the distal esophagus is replaced by a columnar type of epithelium. Although it carries a clear risk of adenocarcinoma, the estimation of this risk and therefore the value of endoscopic screening remain highly controversial.
Aim: To investigate more sensitive techniques to identify those patients who are at high risk of developing cancer and who need intensive endoscopic surveillance for early detection.
Methods: A morphologic, histochemical and morphometric study was performed on paraffin-embedded material from 120 patients with Barrett's esophagus and 18 with adenocarcinoma. In addition, each sample was analyzed immunohistochemically with proliferating cell nuclear antigen (PCNA), p53, c-erbB-2, CEA and EMA antibodies.
Results: In all zones of the glandular mucosa we found a higher percentage of PCNA-positive nuclei when the specialized epithelium was present. We saw PCNA expression in 75% of the patients with adenocarcinoma, and p53 expression in 15% of the patients without dysplasia, 37% of the patients with dysplasia and 44% of the patients with adenocarcinoma. Positivity for c-erbB-2 was found in 38% of the patients without dysplasia, 53% of those with dysplasia and 37% of those with adenocarcinoma. Aneuploidy was found in 70% of the patients with metaplasia or dysplasia and in all patients with adenocarcinoma.
Conclusions: We conclude that p53, PCNA overexpression and aneuploidy are markers of risk for malignancy in Barrett's esophagus.