Synopsis
Recognise mass-effect and seizure presentations, obtain urgent stabilising imaging and definitive tissue safely, integrate histology with molecular classification and coordinate maximal safe surgery, radiotherapy, systemic treatment, rehabilitation and long-term neuro-oncology support.
- Primary brain tumours present through seizures, progressive focal deficits, cognitive or personality change, raised intracranial pressure or an incidental imaging finding.
- Acute deterioration requires non-contrast CT first because it quickly detects haemorrhage, hydrocephalus, marked mass effect and a lesion needing urgent neurosurgery.
- Contrast-enhanced MRI is the preferred definitive imaging test for characterising and mapping a suspected primary brain tumour; include diffusion and other protocol sequences.
- A scan cannot reliably define tumour lineage. The diagnostic reference standard for most infiltrative tumours is neurosurgically obtained tissue sufficient for integrated histological and molecular classification.
- Maximal safe resection is preferred when feasible because it relieves mass, obtains tissue and improves control, but preservation of language, motor, visual and cognitive function limits extent.
- Use neuronavigation, functional MRI, tractography, intraoperative mapping, awake surgery and fluorescence guidance selectively to maximise resection without disabling injury.
- Adult diffuse glioma reports must integrate IDH status, 1p/19q codeletion where relevant and other defining molecular features; MGMT promoter methylation predicts temozolomide benefit in glioblastoma.
- First-line fit-adult glioblastoma treatment is maximal safe resection or biopsy followed by 60 Gy in 30 fractions with concurrent daily temozolomide, then adjuvant temozolomide.
- Give Pneumocystis prophylaxis and monitor blood counts during concurrent temozolomide and radiotherapy according to protocol; lymphopenia may persist.
- Dexamethasone treats symptomatic vasogenic oedema, not the tumour. Use the lowest effective dose and taper promptly to reduce infection, hyperglycaemia, myopathy, psychosis and adrenal suppression.
- Do not give antiseizure medication routinely to every seizure-naive patient; after a tumour-related seizure, a low-interaction agent such as levetiracetam is commonly first line.
- If primary CNS lymphoma is plausible and the patient is neurologically stable, withhold corticosteroid until stereotactic biopsy because lymphoma cells may lyse and yield a non-diagnostic sample.
- Meningioma, glioma, ependymal, embryonal, germ-cell, sellar and nerve-sheath tumours follow different surgery, radiotherapy and systemic pathways; the MDT must not treat a radiological label as a final diagnosis.
- Early rehabilitation, neuropsychology, seizure and driving advice, endocrine review, work support and palliative care are core brain-tumour treatment rather than optional aftercare.
Key red flags
A first focal or generalised seizure in an adult requires urgent assessment for a structural lesion and appropriate brain imaging.
Progressive morning headache with vomiting, papilloedema, altered behaviour, cognitive decline or focal deficit suggests raised intracranial pressure rather than uncomplicated primary headache.
Rapidly falling consciousness, unequal pupils, extensor posturing or Cushing physiology indicates impending herniation and needs immediate neurosurgical escalation.
A posterior-fossa mass can cause abrupt obstructive hydrocephalus, gait ataxia, cranial-nerve signs and vomiting with limited warning.
New focal weakness, aphasia or visual loss may mimic stroke; acute CT is required, but subacute progression or an infiltrative lesion warrants contrast MRI.
Steroid-responsive enhancement does not prove lymphoma, but unnecessary dexamethasone before biopsy can make primary CNS lymphoma temporarily disappear histologically.
Fever, immune suppression or recent infection with a ring-enhancing lesion raises cerebral abscess or opportunistic infection and requires urgent microbiological and neurosurgical input.
Investigation priorities
Rapidly detect haemorrhage, hydrocephalus, calcification, major oedema and midline shift in an acutely unwell patient.
Characterise enhancement, diffusion, infiltration, haemorrhage, perfusion and anatomical relationship for biopsy, resection and radiotherapy planning.
Management branches
A patient has reduced consciousness, progressive deficit, severe vomiting, hydrocephalus or marked imaging mass effect.
- Use ABCDE care, elevate the head, avoid hypoxia and hypotension, treat seizures and obtain urgent CT while contacting neurosurgery and neurocritical care.
- Give dexamethasone for clinically important vasogenic oedema unless stable suspected lymphoma makes diagnostic preservation the higher priority, and treat hydrocephalus with urgent CSF diversion when indicated.
- Proceed to decompression, resection or biopsy according to anatomy and physiology, preserving tissue for integrated pathology before starting tumour-specific therapy.