IMMUNOEXPRESSION OF EGFR AND VEGF PROTEINS IN ORAL CAVITY LIPOMAS
Mesenchymal neoplasm; Oral lipoma; Growth factor receptor; angiogenesis; angiogenic index
Lipomas are the most common benign mesenchymal neoplasms. He has a predilection for the trunk, shoulders, neck and armpit, being rare in the hands, lower legs and feet. The head and neck region is responsible for 20% of cases of lipomas. The oral cavity is responsible for 1-4% of all tumors, affects female and male in a similar way, affecting a wide age group, which varies mainly between the second and ninth decades of life. The etiopathogenesis of this tumor remains unknown, so this research aimed to analyze the expression of EGFR and VEGF, using the immunohistochemistry technique, in oral lipomas and to verify whether their expressions are associated with clinicopathological data. The sample consisted of 54 oral lipomas (33 classic and 21 non-classic) and 23 cases of normal adipose tissue. The analysis of the immunohistochemical expression of EGFR and VEGF was based on that of the cytoplasmic membrane and / or nucleus. The angiogenic index was assessed using microvascular counting (MVC). Cell counting was performed using IMAGE J® software. The data obtained were analyzed using the Statistical Package for Social Science software. The level of significance of 5% was adopted for the statistical tests (p ≤ 0.05). Protein immunoexpression analysis revealed a statistically significant difference for EGFR (p=0.041) between classic lipoma and normal adipose tissue. Regarding the microvessel count, the MVC of non-classic lipomas showed a statistically significant difference (p=0.018) in relation to normal adipose tissue. In non-classic lipomas, only the VEGF immunoexpression was directly proportional to the MVC found in the neoplasia, with a moderate, positive and significant correlation (p=0.010). Furthermore, in classic lipomas it was noticed that the immunomarked adipocytes for EGFR were directly proportional to the immunoexpression of VEGF, this is due to the moderate, positive and statistically significant correlation (p=0.005). Based on the results, it can be concluded that although EGFR, VEGFR and MVC participate in neoplastic development, it is possible to suggest that in lipomas, these proteins and the angiogenic index are not primarily involved in tumor growth.