Determining the probability of malignant transformation of tobacco-induced oral leukoplakia using tissue p53 as a prognostic marker - A cross-sectional study

Context: The concept of field cancerization necessitates substantiation of clinical assessment and histopathological examination by molecular markers. Molecular tumor biomarkers such as p53 protein overexpression aid in assessing the malignant transformation of such potentially malignant oral lesions. Aim: To identify the molecular changes in oral leukoplakia by studying the immunoexpression of tissue p53 and correlating it with the clinical and histological findings to establish an appropriate treatment plan. Methods and Material: Biopsy samples taken from 25 oral leukoplakia cases were subjected to histopathological and immunohistochemical analysis to determine the percentage positivity of p53 expression. Histopathological grading was based on dysplastic features and level of epithelial involvement. Dysplasia grading in IHC sections was estimated by p53% positivity in the cells. The obtained data were subjected to statistical analysis. Results: 24 samples were considered for statistical analysis due to the loss of epithelium in the IHC section of one sample. The results showed a statistically significant association between histopathological and IHC grading of dysplasia with a P value less than 0.05 in Fisher Exact test. Conclusion: Increased expressions of p53 in potentially malignant oral lesions are proportional to the risk of malignancy. The gold standard histopathological result does not reveal the molecular abnormality associated with a potentially malignant oral lesion. Therefore molecular analysis of such lesions will aid in the effective prevention of oral cancer.