Secretory meningiomas: clinical and immunohistochemical observations

OBJECTIVE: Secretory meningiomas are a rare histological subtype of these b enign intracranial tumors. Few reports have been published regarding their tendency to develop peritumoral edema. METHODS: Between July 1994 and February 1999, 11 patients with secretory me ningiomas underwent operations in the Department of Neurosurgery, Universit y of Kiel, Kiel, Germany. The clinical notes and radiological data (compute d tomographic and magnetic resonance imaging scans) were reviewed. Immunohi stochemistry was used to examine the expression of carcinoembryonic antigen and epithelial membrane antigen as well as progesterone and estrogen recep tors. RESULTS: Secretory meningiomas were found in 11 (5%) of 214 patients with i ntracranial meningiomas who were operated on in that period. All 11 patient s were women. These patients' mean age was 65 years (range, 51-87 yr). The localization of these tumors was at the convexity in seven patients, at the sphenoid ridge in two patients, and in the olfactory groove and petrocliva l region in one patient each. Two meningiomas had no edema surrounding them , two meningiomas had a small amount of edema, two had moderate edema, and five had severe edema. No recurrences were observed during the mean follow- up period of 26 months (range, 8-65 mo). Immunohistochemically, all tumors contained pseudopsammoma bodies and reacted with epithelial membrane antige n and carcinoembryonic antigen. The MIB-1 antibody staining index showed a mean of 2% (range, 0-7%). CONCLUSION: Secretory meningiomas are rare tumors, and they are mainly loca lized at the frontal convexity and the sphenoid ridge. They are surrounded by more edema than usual. The preponderance of female patients with this pr esentation is striking. The expression of carcinoembryonic antigen and epit helial membrane antigen is a characteristic feature of secretory meningioma s. These meningiomas are also positive for progesterone receptors, which ha s been shown to be a good prognostic factor.