391 P53 AS A UTILITY MARKER FOR RISK ASSESSMENT IN BARRETT’S OESOPHAGUS

Abstract   Staging and prognosis of a case of Barrett's oesophagus is done by identifying the presence and grade of dysplasia. However, this method is highly subjective and can yield inaccurate diagnoses and prognoses. Demonstration of accumulation of p53 protein may be the most accurate and definitive approach to prognosticating cases of Barrett's oesophagus. This study focuses on p53 protein as a biomarker by immunohistochemistry staining in slides of different progression and demonstrates its promising clinical application. Methods Of 6175 endoscopies, from 970 cases of oesophagitis, a pilot study was performed on 6 cases of pathologically proven Barrett’s oesophagus, including a case with low-grade dysplasia, a case with high grade dysplasia and one case of poorly differentiated adenocarcinoma. Formalin fixed paraffin embedded tissue sections of the above cases were stained for anti p53 antibodies. The elevated immunohistochemical expression was quantified microscopically and a comparative analysis was done. Results p53 staining analysis showed significant immunoreactivity in the case of adenocarcinoma of oesophagus with diffuse strong nuclear staining. Low grade dysplasia and high grade dysplasia showed strong nuclear staining in the involved epithelium with focal and variable intensity positivity in the metaplastic epithelium. Those of reflux oesophagitis showed no nuclear staining in the epithelium. This pattern of staining with histological correlation is in concordance with other similar studies done supporting p53 as one of the crucial biomarkers for increased risk for carcinoma. Conclusion Increased p53 expression shows association with the higher risk of histological progression in the Barrett’s- carcinoma sequence. With the available literature p53 immunohistochemical staining along with other biomarkers will help us to predict the high risk patients and help treating clinician follow up the high risk patients. p53 shows promising utility as a part of panel for Barrett’s oesophagus and the spectrum.