IMMUNOHISTOCHEMICAL ANALYSIS OF ORAL MUCOSA LEUKOPLAKIA

In recent years, substantial changes have occurred in the structure of oral mucosa diseases, in particular an increased ratio of precancerous diseases, so that an effective non- invasive detection of any sign of malignancy appears as an urgent and most actual task of dentistry. Aim: To study the proliferative activity of epithelial cells in Ki-67 antigenin patients with leukoplakia of the oral mucosa. Materials and method: A complex clinical and laboratory examination was performed on 155 patients with oral leukoplakia, who addressed the Operative Dentistry Department of the "A. A. Bogomolets" National Medical University of Kiev between 2010 and 2014. All patients have been subjected to a careful clinical examination, which included: dental anamnesis, visual inspection, oral examination and digital palpation of oral mucosa and tongue mucosa, biopsy of leukoplakia lesions for cytological and histological examination. Results: Histological evaluation of the material has been performed according to the WHO (2005) classification of leukoplakia. 10 (14%) sites of unaltered mucosa, 10 (14%) samples of hyperkeratosis without atypia, 14 (19%) biopsy specimens of hyperkeratosis SIN1, 15 (21%) hyperkeratosis SIN2, 10 (14%) - SIN3 and 13 (18%) cases of squamous cell carcinoma were evidenced. Immunohistochemical investigation evidenced the presence of protein Ki- 67 in the nuclei of epithelial cells. In the unmodified epithelium of the oral mucosa, all epithelial cells with stained nuclei are virtually located in the basal layer. Conclusion: Against the general increase of the proliferative activity of epithelial cells with increasing SIN, a characteristic distribution of proliferating cells in the thickness of the epithelium was revealed for each studied group, as follows: in the control group and in leukoplakia without atypia, immunopositive cells are located in the basal layer, in leukoplakia (SIN1, SIN2 and SIN3) - in parabasal position while, in squamous cell carcinoma of oral mucosa, the distribution was uniform.