Expression of Ki-67 and p53 in meningiomas.

UNLABELLED: Meningiomas account for about 30% of all primary brain tumors. It is difficult to predict the behaviour of meningiomas, and identification of protein markers responsible for the regulation of cell proliferation can be very helpful. The aim of this study was to evaluate immunohistochemical expression of Ki-67 and p53 in 170 meningiomas.A total number of 170 meningioma samples were classified according to WHO, immunohistochemically stained for Ki-67 and p53 and analysed using light microscope. Of 170 meningiomas analysed, 142 were grade I, 17 grade II and 11 grade III. Female to male ratio was 1.42:1. Statistically significant correlation was found between tumor grade and Ki-67 (p<0.001). There was significant correlation between Ki-67 levels and tumor subtypes (p=0.009). The optimal cut-off value for Ki-67 was 3.195. Tumors with Ki-67 ≤3.195 were 2 cm smaller than tumors with Ki-67 >3.195. Statistically significant correlation was found regarding p53 expression and tumor size (p=0.034). No correlation was established between Ki-67 or p53 and location of the tumor.According to positive correlation between tumor grade and subtype with Ki-67 levels, as well as positive correlation between Ki-67 and p53 with tumor size, indicate that Ki-67 and p53 might have influence on meningioma development and progression. KEYWORDS: meningioma, Ki-67, p53, immunohistochemistry.