Synopsis
Recognise brain metastases and acute mass effect, investigate intracranial and extracranial disease, and reason through systemic therapy, surgery, stereotactic treatment, whole-brain radiotherapy and supportive care using patient-specific factors.
- Brain metastases are secondary tumours arriving mainly by the bloodstream; common primaries include lung, breast, melanoma, renal and gastrointestinal cancers, but any cancer history must be interpreted with the scan and current pathology.
- Symptoms reflect lesion location, number, haemorrhage, oedema and CSF obstruction; a patient can have a solitary dominant lesion or numerous small metastases.
- Symptomatic brain metastases should receive local therapy when appropriate regardless of systemic therapy; urgent mass effect needs immediate neurosurgical and oncological assessment.
Key red flags
New focal deficit, seizure, cognitive change, gait dysfunction or persistent headache in a person with current or previous cancer.
Falling consciousness, pupil change, repeated vomiting or rapid motor decline indicating mass effect or acute haemorrhage.
A solitary or dominant large lesion with oedema and mass effect that may benefit from surgical decompression and tissue diagnosis.
New neurological symptoms during surveillance after treatment, which require clinical review and appropriate imaging rather than waiting for the next scheduled visit.
Back pain, radicular symptoms, sphincter change or limb weakness suggesting separate spinal metastatic disease or cord compression.
Leptomeningeal symptoms such as multifocal cranial neuropathies, radicular pain or widespread neurological deficits, which follow a different investigation and treatment pathway.
Characterise focal onset, duration, recurrence and residual deficit. Ongoing seizure or incomplete recovery requires emergency treatment and imaging, while a recovered first seizure still needs prompt structural evaluation.
Progressive headache, vomiting, drowsiness, papilloedema or pupil change can reflect oedema or hydrocephalus; abrupt severe symptoms may indicate intratumoural haemorrhage.
Investigation priorities
Detect haemorrhage, hydrocephalus, major oedema and mass effect rapidly in an acutely deteriorating patient.
Management branches
A patient with cancer develops progressive hemiparesis and MRI shows one accessible large lesion with substantial oedema.
- Assess emergency pressure signs, seizure, function and reversibility, and involve neurosurgery, radiation oncology and the primary-tumour team promptly.
- Review extracranial control, performance status, lesion location and operative risk while treating acute symptoms; symptomatic disease should not wait for systemic therapy alone.
MRI shows several lesions in a person who is stable enough for full multidisciplinary selection.