Last reviewed 01/2018

These are tumours of the oligodendrocytes and account for approximately 10% of primary intracranial tumours. They are most common between the ages of 30 and 50 years. They arise mainly in the frontal lobes, and occasionally in the ventricular walls where they may seed the CSF.

The majority are slowly growing but some may show malignant change which results in a histological picture similar to that of the glioblastoma multiforme.

Presentation is usually with seizures though some may have slowly developing focal signs. CT shows well demarcated lesions and commonly, calcification.

The preferred treatment is by surgical excision since radiotherapy is unproven. Median survival is 5 years but may reach 20 years in non-astrocytomal-like lesions.