[Cytokeratin and p53 expression of odontogenic cysts]

The histopathologic diagnosis of odontogenic cysts is based mainly on the morphological nature of the epithelial lining of cysts and their origin. We used the international histologic classification set up by the World Health Organisation in 1992. The aim of this study was to investigate the differentiation of various types of cyst using an immunohistochemical technique rather than by conventional morphological assessment. A standard immunocytochemical method (APAAP method), applying anticytokeratin monoclonal antibodies and a p53 antibody, was used for the diagnosis of odontogenic cysts. A total of 57 jaw cysts were diagnosed according to clinical, radiological and pathological criteria as radicular cysts (20), dentigerous cysts (20) and keratocysts (17). The results proved that cyst type can be distinguished by the pattern of staining using the monoclonal antibodies CK7, CK19, CK20 for cytokeratins and the clone DO-7 for the p53 protein. Staining with the monoclonal antibodies CK7 and CK20 did not distinguish type. CK19 was not detected in keratocysts and p53 was only expressed in keratocysts. This may prove to be diagnostically useful for the more precise distinction between different cyst types.