AMELOBLASTOMA ARISING IN ODONTOGENIC KERATOCYST: REPORT OF FOUR RARE CASES, IMMUNOHISTOCHEMICAL ANALYSIS AND REVIEW OF LITERATURE

Materials and Methods:10 cases each of AEP, IPH and PSCC were retrieved from the University of Florida, Oral Pathology Biopsy Service archive and stained with Anti-KMT6/EZH2 antibody.The cases were reviewed and the extent and pattern of EZH2 expression were assessed.The results were analyzed for statistical significance using Fischer's exact test.Results:The pattern and intensity of EZH2 expression in AEP and PSCC demonstrated statistically significant differences when compared to IPH (p=0.002).In addition, the basal cell layer showed EZH2 expression in all the cases of AEP (100%) and PSCC (100%) but only 3 out of 10 (30%) in IPH (p=0.000),comparable to normal oral epithelial control tissue. Conclusion:EZH2 expression in AEP is more similar to malignant processes than benign lesions.The pattern of basal cell layer expression of EZH2 could be a potential prognostic indicator of malignant transformation risk in oral AEP lesions.A subsequent study by our group to assess EZH2 expression with respect to clinical outcome in AEP lesions is ongoing.