Related Experiment Videos
Secretory meningioma: clinical, histologic, and immunohistochemical findings in 31 cases
S Probst-Cousin1, R Villagran-Lillo, R Lahl
1Institute of Neuropathology, University Hospital, Münster, Germany.
Background:
Secretory meningioma is a rare histologic variant characterized by a unique epithelial differentiation of meningothelial cells resulting in the production of hyaline inclusions. Most previous reports have presented single case observations. The authors selected 31 cases for a clinicopathologic study to characterize this type of tumor further.
Methods:
Clinical data were compiled and the extent of peritumoral edema was assessed from preoperative computed tomography or magnetic resonance imaging scans. Preparations of surgical specimens of all tumors were studied after both conventional histologic and immunohistochemical preparations were made. Immunostaining was performed by either the avidin-biotin complex method or the alkaline phosphatase-antialkaline phosphatase method using 22 primary antibodies.
Results:
In the tumor collection used in this study, secretory meningiomas represented 3% of meningiomas. The female-to-male ratio was 9:1. Most tumors were located at the sphenoid ridge or at the frontal convexity, and recurrences were not observed. Eighty-four percent of tumors presented with slight to marked peritumoral edema. The MIB-1 staining index showed a mean of 3.8%. Inclusions and surrounding cells consistently expressed epithelial membrane antigen, cytokeratins, carcinoembryonic antigen, and carbohydrate antigen 19-9. In decreasing frequency, they also contained alpha1-antitrypsin, immunoglobulin (Ig)A, alpha1-antichymotrypsin, IgM, and IgG. Cells positive for vimentin and S-100 did not contain inclusions. All tumors were positive for progesterone receptors. Macrophages were stained with antibodies to factor XIIIa, human leukocyte antigen-DR, and alpha1-antitrypsin. In 64% of cases, tumor vessels lacked expression of glucose transporter protein 1.
Conclusions:
The classification of secretory meningioma as a distinct variant has been justified on clinical, histologic, and immunohistochemical grounds. The unique epithelial features call attention to the broad spectrum of differentiation properties found in meningiomas.
Insights
Secretory meningiomas, a rare tumor variant, exhibit distinct epithelial features and are confirmed as a separate type through clinical and immunohistochemical analysis. These tumors show specific protein expressions and are associated with peritumoral edema.
Area of Science:
- Neurosurgery
- Pathology
- Oncology
Background:
- Secretory meningioma is a rare histologic variant of meningioma.
- Characterized by epithelial differentiation and hyaline inclusions.
- Previous reports primarily focused on single case observations.
Purpose of the Study:
- To further characterize secretory meningioma.
- To conduct a clinicopathologic study of 31 cases.
- To establish the distinct nature of this tumor variant.
Main Methods:
- Compiled clinical data and assessed peritumoral edema from imaging (CT/MRI).
- Performed conventional histology and immunohistochemistry on 31 surgical specimens.
- Utilized 22 primary antibodies for immunostaining (avidin-biotin or AP-ABC methods).
Main Results:
- Secretory meningiomas constituted 3% of all meningiomas, with a 9:1 female-to-male ratio.
- Commonly located at the sphenoid ridge/frontal convexity; no recurrences observed.
- Exhibited epithelial differentiation markers (EMA, cytokeratins) and specific protein expressions (CEA, CA19-9, A1AT, IgA, AACT, IgM, IgG).
- 84% showed peritumoral edema; MIB-1 index averaged 3.8%.
- Tumor vessels lacked GLUT1 in 64% of cases.
- All tumors expressed progesterone receptors.
Conclusions:
- Classification as a distinct variant is supported by clinical, histologic, and immunohistochemical findings.
- Highlights the diverse differentiation potential within meningiomas.
- Epithelial features underscore the unique nature of secretory meningioma.