Expansion
Metastases outnumber primaries, and glioblastoma is the commonest primary
Expansion
Metastases are the commonest intracranial tumours: lung, breast, melanoma, renal and colorectal, typically multiple and at the grey-white junction.
Primary tumours
- Glioblastoma (grade 4 astrocytoma) - the commonest primary in adults. Butterfly spread across the corpus callosum, ring enhancing with central necrosis, pseudopalisading necrosis histologically. Poor prognosis
- Meningioma - the commonest benign tumour. Extra-axial, dural based with a dural tail, psammoma bodies, commoner in women
- Oligodendroglioma - fried egg cells, calcification, frontal lobe, 1p/19q codeletion predicting chemosensitivity
- Vestibular schwannoma - cerebellopontine angle, S100 positive, bilateral in neurofibromatosis type 2
- Pituitary adenoma - bitemporal hemianopia, endocrine effects
In children, tumours are usually infratentorial
- Pilocytic astrocytoma - the commonest, cystic with a mural nodule, Rosenthal fibres, good prognosis
- Medulloblastoma - highly malignant, cerebellar, seeds through the CSF, small blue cells with Homer Wright rosettes
- Ependymoma - fourth ventricle, causing hydrocephalus
Presentation: raised intracranial pressure (headache worse on waking and on coughing, vomiting, papilloedema), seizures, and progressive focal deficit.