Angiogenesis in salivary gland mucoepidermoid carcinoma and its relation to histologic grading

ABSTRACT

Angiogenesis is known as the outgrowth of new blood vessels from preexisting vasculature and plays an important role in different aspects of tumor growth and metastasis. Microvessel density [MVD] represents angiogenesis in neoplastic tissues and is generally employed as a useful tool for its measurement. The aim of the present study was to evaluate MVD in salivary gland mucoepidermoid carcinomas [MECs] and to assess its relation to histologic grade. In this cross-sectional study, 30 parotid and minor salivary MECs were graded under a light microscope according to the AFIP criteria. All specimens were immunohistochemically stained with monoclonal antibody against CD34. MVD was determined by counting all positively-stained cells or cell clusters in 10 high-power-fields, selected from the most vascularized areas. The results were analyzed using one-way ANOVA and Scheffe post-hoc tests. MVD was expressed as the mean number of microvessels per high-power-field. A statistically significant correlation was observed between MVD and MEC grade [P=0.001]. Microvessel density was significantly lower in grades I [11.12] and II [13.66] compared to grade III [23.50] tumors. The difference between grades I and II neoplasms was not significant [P=0.725]. According to the results obtained in the present study angiogenesis may have an important role in the pathogenesis of parotid and minor salivary gland MEC and may be useful in the prediction of its biologic behavior