Surgical Management of Pilocytic Astrocytoma of the Optic Nerve: A Case Report and Review of the Literature

Table 1

Selected CNS gliomas. Comparison of basic histopathologic findings and immunostaining characteristics.

Selected CNS tumor	WHO grade	Histopathology	MIB-1/Ki-67 LI	p53
Pilocytic astrocytoma	I	Biphasic piloid and spongy glial cell regions	<10%	<5%
Diffuse astrocytoma	II	+ Diffuse infiltration and cytoplasmic atypia	<10%	<5%
Anaplastic astrocytoma	III	+ Anaplasia and high mitotic activity	>10%	>5%
Glioblastoma	IV	+ Microvascular proliferation and/or necrosis	>10%	>5%
Ganglioglioma	I	Uniform, monomorphic glial cell and ganglion cell components, diffuse infiltration, and rare mitosises	<5%	<5%
Anaplastic ganglioglioma	III	+ Anaplasia, increased mitotic activity, vascular proliferation, and necrosis	>5%	>5%

Immunostaining characteristics are general guidelines and must be utilised in conjunction with histopathologic features.