Epithelial-myoepithelial carcinoma harboring p53 mutation

A case of epithelial-myoepithelial carcinoma of the parotid gland harboring p53 mutation is reported. The tumor removed from a 67-year-old Japanese fe male was composed of an organoid biphasic population of cells: inner dark e pithelial cells were surrounded by clear myoepithelial cells. The cells wer e immunopositive for EMA and smooth muscle actin, respectively. Some of the epithelial cells formed solid nests. Immunostaining for proliferating cell nuclear antigen (PCNA) resulted in a higher percentage of labeled cells in the solid epithelial region than in the region with the more general bipha sic pattern. Genetic analysis, including polymerase chain reaction-single s trand conformational polymorphism (PCR-SSCP) and nucleotide sequencing, rev ealed a I-nutation in codon 207 (aspartic acid to glycine) of the p53 tumor -suppressor gene. To our knowledge, this is the first report of a mutation in the p53 gene in an epithelial-myoepithelial carcinoma of the salivary gl and.