Immunohistochemical expression of progesterone and estrogen receptors in meningiomas.

In this study we present results of investigations of progesterone and estrogen receptors in most frequent, WHO grade I histological types of meningiomas (meningothelial, fibrous, and transitional) and in atypical--WHO grade II variant of these tumors. Samples from 64 tumors were examined. The cohort consisted of 46 WHO grade I (21 transitional, 13 fibrous and 12 meningothelial histologic variants) and of 18 atypical meningiomas. Apart from immunohistochemical examination of progesterone and estrogen receptors, MIB 1 labeling index was estimated. Positive immunoreaction for progesterone receptors was found in 100% meningothelial, 95% transitional, 46% fibrous and 78% atypical variant of meningiomas. Intensity of immunoreaction was stronger in grade I than in grade II tumors. Immunoexpression of estrogen receptors was found in 48% of the investigated meningiomas. No correlation was stated between WHO grade I and grade II tumors, and between meningothelial, transitional and fibrous variants of the neoplasms.