Estrogen and progesterone receptors in meningiomas: immunohistochemical (Mib-1, p53) and clinico-morphological correlations

We studied 98 meningiomas including 89 benign, 5 atypical, and 4 anaplastic tumors to determine the immunohistochemical expression of estrogen and progesterone receptors and its prognostic value in comparison to histological grade, Mib-1 and p53. Estrogen and progesterone receptor positivity was observed in 63% and 5% of the cases, respectively. In 79% of meningiomas only a minimal proliferative activity was documented, whereas in 36% we detected an overexpression of the p53 oncoprotein. Anaplastic meningiomas were constantly negative for PgR, ER, and highly positive for Mib-1; 75% were positive for p53. A statistical correlation was demonstrated between p53 protein and Mib-1. Specifically the p53-negative meningiomas were frequently negative for Mib-1 (p = 0.002); conversely the lesions strongly positive for Mib-1 were p53-positive (p = 0.001).