General points
Clinical presentation
- very variable according to parts of brain involved and nature of the tumour
- symptoms can be caused by local brain invasion, raised intracranial pressure and compression of adjacent structures
- headache – dull, constant or throbbing, progressive, may be worse at night waking the patient
- seizures – nature depends on location of tumour
- focal deficits – weakness, sensory loss, aphasia
Investigation
- full neurological exam to evaluate any potential deficits +/- ophthalmoscopy if suspecting raised intracranial pressure
- MRI + contrast
- biopsy required for histopathologic diagnosis and grading
Management
- often requires complex decision by multidisciplinary team, considering relative benefits of neurosurgery, radiotherapy and chemotherapy
- depending upon tumour site, endocrine or ophthalmological input may also be required
- options for treating symptoms: dexamethasone if significant oedema causing symptoms (avoid if suspecting lymphoma); anti-epileptics
Brain Metastases
- commonest form of brain tumour
- increasing incidence of brain metastases due to better treatment of primary tumours/patients surviving longer
- common primary sites = lung, melanoma, breast
- very variable presentation – low threshold for investigating people with known primary cancer
Imaging
- usually rounded, well circumscribed masses
- CT brain + IV contrast – contrast needed to show up mets
- +/- MRI – for solitary lesions to assess resectability, also for better brainstem visualisation
- staging CT
Management
- whole brain radiotherapy
- poor prognosis – aggressive treatment only considered in very young/fit patients
- neurosurgery indications: ≤3 metastases, palliation of hydrocephalus/debulking large metastases, biopsy for histological Dx (if unknown 1ry)
- stereotactic radiosurgery – gamma knife, linear particle accelerator
Primary brain tumours
Meningioma
- approximately 1/3 primary CNS tumours
- more commonly older and female patients
- associations – radiation exposure, neurofibromatosis type 2
- attached to dura (10% arise in spinal cord)
- slow growing, often asymptomatic and discovered incidentally (so true incidence may be even higher than current estimations)
- MRI – homogeneous contrast enhancement after gadolinium
- Management – small tumours can be managed conservatively, large or symptomatic tumours may require surgery

Menigioma – image from Wikimedia Commons, used under creative commons license.
Meningioma – image from radpod.org, used under creative commons license.
Gliomas
General points
- approximately 1/3 primary CNS tumours
- gliomas generally fast growing and in younger patients
- many different types depending upon glial cell of origin
- management – usually aim for full resection of tumour where possible
Astrosytoma
- grades I+II = commoner in children
- grade IV = glioblastoma multiforme – commonest adult form, heterogeneous appearance, very poor prognosis

Glioblastoma multiforme – image from radpod.org, used under creative commons license.

Glioblastoma multiforme – image from Wikimedia Commons, used under creative commons license.
Oligodendroglioma
- better prognosis than astrocytomas
- characteristic molecular abnormalities: IDH1/2 mutation & co-deletion of chromosomal arms 1p and 19q
Ependymoma
- arise from cells lining ventricles
- obstructive hydrocephalus a potential complication
- generally low-grade, but commonly more aggressive in children with posterior fossa tumour

Ependymoma – image from Wikimedia Commons, used under creative commons license.
Schwannoma
- usually benign (only 1% malignant)
- commonly affecting cranial nerves (i.e. intracranial but peripheral nervous system – Schwann cells myelinate peripheral nerves)
- common site = cerebropontine angle
- vestibular schwannoma (acoustic neuroma) = schwannoma of CN VIII – usually older patients, cause sensorineural hearing loss +/- tinnitus
- neurofibromatosis 2 → younger patients with bilateral acoustic neuroma
- other CNs affected: V > VII > IX/X/XI

Vestibular Schwannoma – image from radpod.org, used under creative commons license.
Craniopharyngioma
- very rare, arising from remnants of Rathke’s pouch – migrates between nasopharynx and diencephalon
- more common in children
- visual symptoms caused by compression of optic chiasm – commonly inferior visual field defect due to superior compression

Craniopharyngioma – image from radpod.org, used under creative commons license.
n.b. key facts:
- tumour located next to skull/attached to dura → meningioma
- tumour attached to ventricle wall → ependymoma
- bilateral vestibular schwannomas in young patient → neurofibromatosis type 2