Table 4.

INHAND nomenclature criteria: Malignant oligodendroglioma.

Well-circumscribed lesion with a distinct border, extending over multiple areas of brain (spinal cord)

Characterized by focal or diffuse anaplasia, as evidenced by high cellularity, cellular atypia and pleomorphism, prominent proliferation of glomeruloid vessels at the tumor margins, nuclear polymorphism, increased mitotic index, necrosis, and/or meningeal infiltration

Atypical capillary endothelial hyperplasia (“garlands”), especially at the tumor periphery, is extensive and is a characteristic feature.

Necrosis with cystic changes and hemorrhages is frequent.