ATYPICAL MENINGIOMA WITH LOW GROWTH POTENTIAL

We reported a 63 year-old woman with atypical meningioma. Histopathological findings of this tumor showed increased cellularity, irregularity of nuclear size, mitotic figures, and brain invasion. Neoplastic cells were positively stained for vimentin and S-100 protein immunohistochemically. A small proportion of cells expressed epithelial membrane antigen. The MIB-1 labeling index value of this tumor was 0.93%, and this value is significantly lower than other cases of atypical meningioma. These results indicate that the tumor might be invasive but of low growth potential. Atypical meningioma such as this case could have a better prognosis.