Fragments of soft tissue and lamellar bone with intertrabecular marrow spaces diffusely infiltrated by a hypercellular meningothelial neoplasm. The tumor exhibits a predominant solid, sheet-like growth pattern, lacking classic whorled architecture. The neoplastic cells shows syncytial cytoplasm and demonstrate marked cytologic atypia, including nuclear pleomorphism, hyperchromasia, an increased nuclear-to-cytoplasmic ratio, and prominent macronucleoli. Mitotic activity is readily identified. There is no evidence of spontaneous coagulative tumor necrosis in the examined tissue. The architectural (hypercellularity, sheeting) and cytological (atypia, mitotic activity) features support the diagnosis of an atypical meningioma (WHO Grade 2).
Right sphenoid wing en plaque meningioma with orbital and middle cranial fossa extension.
Soft tissue and bone fragments collectively measured 5x4.5x0.8 cm, totally embedded.
Right sphenoid wing lesion, biopsy: