Plasmacytoid myoepithelioma of the palate. Report of one case and review of the literature

INTRODUCTION: Myoepithelioma is a benign neoplasm of salivary glands, represents 1.5 % of all salivary glands neoplasm. The plasmacytoid myoepithelioma from palate salivary glands is considered as a rare entity, at date it has been reported 14 cases. It is present one case of plasmacytoid myoepithelioma of palate. CASE REPORT: A Hispanic female of 28 years old presented a not-ulcerate, painless ovoid swelling at left side of hard palate with a one year and a half of evolution. An excisional biopsy was done. The sample was fixed at 10% buffer formalin, embedded in paraffin, cuts at 5 micron and stained with H-E. Microscopically, the lesion was composed by myoepithelial neoplastic cells characterized by a round ovoid silhouette, an eccentric nuclei of dense chromatin and eosinophilic cytoplasm. In some myoepithelial neoplastic cells were identifies intranuclear cytoplasmatic inclusions. The lesion was analysed with immunohistochemical technique using the follow antibodies: vimentin, citokeratin AE1/AE3, S100 protein and actin muscle specific. We observe positive immunoreactivity against vimentin, citokeratin, S100 protein and actin muscle specific. A diagnosis of plasmacytoid myoephitelioma of palate salivary glands was done. Our findings supports the suggestion about plasmacytoid myoepithelioma is an independent entity. The histological diagnostic parameters of plasmacytoid myoepithelioma versus pleomorphic adenoma are discussed.