Markeri proliferacije i intermedijarnih filamenata u diferencijalnoj dijagnozi benignih i malignih tumora pljuvačnih žlezda

Abstract

Introduction: Salivary gland tumors are rather rare neoplasms characterized by a high level of pleomorphism and histological overlapping. Very often, one tumor may contain several cell types, therefore, it is necessary to include additional histochemical and immunohistochemical staining, as well as the morphometric analysis of tumor cells, in terms of an appropriate diagnosis. Materials and methods: The research encompassed 30 benign and 30 malignant tumors, including pleomorphic adenoma (10), Warthin’s tumor (10), basal cell adenoma (6), myoepithelioma (4), adenoid cystic carcinoma (6), mucoepidermoid carcinoma (8), salivary duct carcinoma (6), polymorphous low-grade carcinoma (6), and myoepithelial carcinoma (4). The expression of Ki67, p53, HER-2, p63, CEA, EMA, S-100, CK14, WT-1, GFAP, αSMA and vimentin was analyzed. The morphometric analysis was performed using “ImageJ” software pack. The area, perimeter, Feret diameter, integrated optical density, nucleus circularity and roundness were analyzed. Results: The Ki67 proliferative index was statistically significantly higher in malignant tumors (p<0.001). Adenoid cystic carcinoma exhibited the highest value, whereas the lowest value was exhibited by basal cell adenoma. Immunohistochemically, pleomorphic adenomas were positive to S-100, GFAP, CK14, αSMA, WT1 and EMA. Warthin’s tumor was positive to CK14, CEA and p63; basal cell adenoma showed positivity to S-100, CEA, and vimentin, whereas myoepithelial tumors were positive to vimentin, GFAP, S100, CK14, αSMA. Adenoid cystic carcinoma exhibited positivity to CEA and S-100, mucoepidermoid carcinoma to CK14, salivary duct carcinoma to EMA, CEA, p53 and HER-2, while polymorphous low-grade carcinoma exhibited positivity to CK14, p63, EMA, S100 and vimentin. The morphometric analysis showed statistically significantly increased values of integrated optical density (p<0.001) and nuclear size parameters (p<0,05) in malignant tumors. The highest values for all parameters were exhibited by salivary duct carcinoma Conclusion: The immunohistochemical analysis was used to determine tumor histogenesis with the aim of differentiation. The Ki67 proliferative index is highly useful in the differentiation of benign from malignant tumors. The morphometric parameters of integrated optical density and nuclear size show statistically higher values in the malignant tumor group.