Application of immunohistochemical markers in diagnostics of various histological types of pleomorphic adenomas of the salivary glands

Abstract

Summary. The morphological verification of tumors as a diagnostic method has been the basis for establishing the final diagnosis for a long time. According to various data, the accuracy of the diagnosis ranges from 80–85 %, depending on the type of tumor (benign or malignant) and its differentiation. With the introduction of immunohistochemical studies for the final diagnosis of tumors, the percentage of verified tumors has increased significantly. The aim of the study – determination of peculiarities of pathogenesis of various histological types of pleomorphic adenomas of the salivary glands applying the methods of immunohistochemical diagnostics. Materials and Methods. The study was conducted based on the excisional biopsies of the pleomorphic adenomas of the salivary glands in 28 patients. The immunohistochemistry analyses were performed with Monoclonal Mouse Anti-Epstein Barr Virus, Polyclonal Rabbit Antibody p16, Monoclonal Rabbit Anti-Human Estrogen Receptor (ER), and the Mouse Anti-Human Progesterone Receptor (PR), PLAG1 (pleomorphic adenoma gene 1) Monoclonal Antibody. Results and Discussion. The results of the conducted study of the own surgical material show that the structure of histological types of pleomorphic adenomas of the salivary glands is as follows: mesenchymal 15 (53.57 %), epithelial-mesenchymal – 10 (35.47 %), epithelial – 3 (10.71 %). The mesenchymal and epithelial-mesenchymal types of histological structure of pleomorphic adenomas of the salivary glands are characterized by the similar immunohistochemical peculiarities (Plag1 – positive response in tumor cells of both histological types in 100 % of cases; HPV 16 – 73.33 % and 80.0 % respectively and EBV – 33.33 % and 30.0 % respectively). The epithelial type of structure of the pleomorphic adenomas of the salivary glands is characterized by slightly different immunohistochemical pattern: Plag1 – positive response in tumor cells in 66.66 % of cases; HPV 16 – also in 66.66 % of cases. The mesenchymal and epithelial-mesenchymal types of histological structure of pleomorphic adenomas of the salivary glands are characterized by more frequent invasion of HPV 16 and EBV. Conclusions. The mesenchymal and epithelial-mesenchymal types of histological structure of pleomorphic adenomas of the salivary glands are characterized by more frequent invasion of HPV 16 and EBV.