Histopathological findings of lesion. (a) Photomicrographs showed that focal hypercellularity and atypia were noted in whitish mass with higher mitotic activity (white arrowed) and enlarged polymorphic nuclei (black arrowed). (b) In some area, the mass was composed of mainly clear cells with small round monomorphic nuclei and abundant clear cytoplasm resembling the histological feature of clear cell variant of meningioma. (c) The adjacent brain parenchyma to the mass and other removed smaller grayish lesion revealed numerous abnormal small intracortical blood vessels, which were cuffed by meningothelial or fibroblasts-like spindle cells with bland nuclei and elongated cytoplasm. (d) The gradual transition from perivascular proliferation of spindle cells to the mass of the meningioma could be observed. (a & b, H&E staining with original magnification of 400×; c, H&E staining with original magnification of 200×; d, H&E staining with original magnification of 100×).
Chen et al. Diagnostic Pathology 2010 5:39 doi:10.1186/1746-1596-5-39