Mioara Trandafirescu, Constantin Cotutiu, Elena Cojocaru, Liliana Foia
Known and described since the nineteenth century as mixed tumour of salivary gland, and subsequently called pleomorphic adenoma, this tumour is a benign lesion with a complex structure, composed of epithelial type areas mixed with fibrous, mucoid or condroid stromal areas. The lesion raised many discussions related to its histogenesis and its possibility of malignancy, talks which currently continue. In order to argue for some of the theories, immunohistochemical reactions with anti-cytokeratin, anti-vimentin, anti-S100 protein, anti-p53 protein, anti-Ki67 protein, and anti-CD34 monoclonal antibodies were used. It was noted that all the cellular components of the lesion respond positively to cytokeratin and vimentin, more intensely in myoepithelial cells and periductular cells. All the proliferation markers were positive in all the cells, regardless of the morphological type and the intensity was increased in cases of malignancy. Thus, our research supports the hypothesis of the unique epithelial histogenesis and the possibility of malignization of pleomorphic adenoma, which differs from the primitive salivary gland carcinomas.