PMC4533486_01
Axial (A) and sagittal view (B) of contrast-enhanced magnetic resonance (MR) images showing an enhanced mass that spreads from the tentorium cerebelli at the straight sinus along the inferior border of the falxcerebri. The inferior sagittal sinus runs through the center of the mass, and a cerebral vein from the vein of Galen runs along the inferior border of the mass.
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F1
Contrast-enhanced MRI showed homogeneous enhancement (Fig. 1).
A: Hematoxylin-eosin (HE) staining at x100 magnification showing the meningioma and proliferation of tumor cells in sheets. B: HE staining at x100 magnification showing the metastatic area and dense epipapillary propagation of tumor cells with nuclear atypia.
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F2
Histopathologic findings included propagation of dense sheets of cells, mostly with ovoid or spindle-shaped nuclei (Fig. 2A); thus, we diagnosed meningothelial meningioma. However, we observed a single area that showed dense epipapillary propagation of tumor cells with nuclear atypia to suspect cancer metastasis (Fig. 2B).
A: CK7 at x100 magnification observed as deep staining in the metastatic area. B: TTF-1 at x100 magnification observed as deep staining in the tumor cells. C: Napsin at x100 magnification observed as deep staining in the tumor cells. D: Tumor cell staining by alcian blue. Original magnification x100. E: E-cadherin at x40 magnification showing positive in both adenocarcinoma (upper side) and meningioma cells (lower side). CK7: cytokeratin 7, TTF-1: Thyroid transcription factor-1.
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F3
An additional immunohistologic examination that included differential diagnosis of papillary meningioma, cytokeratin 7 (CK7) (Fig. 3A), thyroid transcription factor-1 (TTF-1) (Fig. 3B), Napsin (Fig. 3C), and alcian blue (Fig. 3D) showed positive, while S-100 and thyroglobulin were negative. Furthermore, E-cadherin staining showed 70% positive rate in lung adenocarcinoma and 30% in meningothelial meningioma (Fig. 3E).