Diagnostic significance of nuclear p53 expression in the surveillance of Barrett's esophagus - a longitudinal study

The efficacy of currently performed surveillance in patients with Barrett's esophagus (BE) is substantially compromised by shortcomings of dysplastic lesions as diagnostic markers. The aim of this study was to evaluate the po ssible role of p53 protein expression as complementary method in the diagno sis of neoplastic transformation in BE. A longitudinal study was performed. 41 patients were enrolled. The median t ime of surveillance was 46 months. 234 archival paraffin blocks containing a total of 627 biopsies were retrieved. p53 protein immunostaining by appli cation of the monoclonal antibody DO-1 was performed. The results of immuno histochemistry were compared with the exact histopathological diagnosis and grading of dysplasia (no dysplasia, indefinite for dysplasia, low-grade dy splasia, high-grade dysplasia, carcinoma). In merely four of 206 nondysplastic mucosal sites p53 expression was found. However, p53 expression was detected with increasing frequency in sites in definite for dysplasia (2/9), specimens with low-grade dysplasia (9/15), hi gh-grade dysplasia (3/3) and the one with a carcinoma. This study shows a c lose association of nuclear p53 protein expression to the process of neopla stic transformation in Barrett's epithelium. However, it apparently does no t precede the appearance of dysplasia significantly. Thus, nuclear p53 expr ession nas detected by immunohistochemistry may serve to confirm a suspecte d diagnosis of dysplasia in BE.