Table 1.

Summary of intramedullary spinal cord tumors

Tumor type	Gene mutation	Incidence	Clinical implications
High-grade astrocytomas	H3 K27M	About half of spinal high-grade astrocytomas were described to harbor the H3 K27M mutation.	H3 K27M mutation is associated with high malignancy, regardless of the histopathological findings.
Low-grade astrocytomas	BRAF	Although not restricted to spinal cord lesions, more than 75% of PA harbor the KIAA1549-BRAF mutation, and about 6% harbor the BRAF V600E mutation.	KIAA1549-BRAF mutation is correlated with better prognosis.
		The frequency of the mutation in DA is unknown.	BRAF V600E is associated with more aggressive behavior in pediatric low-grade astrocytomas.
	IDH	Although common in intracranial counterparts, it seems to be quite rare in spinal cord lesions.	The relationship with the prognosis in spinal astrocytomas is controversial because of its rarity.
Spinal ependymomas	NF2	NF2 mutation is not apparent in intracranial ependymomas.	Driver mutation for spinal cord ependymomas.
	MYCN amplification	Most likely present in a quite small number of patients in spinal ependymoma.	It has characteristic clinical features and correlates with poor prognosis.
Spinal hemangioblastomas	VHL	Most cases of VHL disease are associated with HB and some patients with sporadic HB carry the VHL mutation.	Benign vascular lesion.

PA, pilocytic astrocytoma; DA, diffuse astrocytoma; HB, hemangioma.