Initial management requires control of the presenting symptoms, with anti-convulsants, analgesics, and other medication as appropriate. Dexamethasone is indicated in the majority of patients and frequently produces a reversal of symptoms. A starting dose of 8-16 mg daily is common and improvement can often be maintained with doses of 2-4 mg. The failure of a response to dexamethasone may be an argument against more aggressive therapy.

Since the outcome for patients with multiple adverse prognostic factors is so poor, irrespective of treatment, it is reasonable to manage those individuals with symptomatic therapy alone. For patients whose condition is improved following dexamethasone, treatment with radiotherapy can be offered. This approach may produce temporary tumour control, improve survival, and allow a reduction in the steroid dose. Typically, the whole brain is irradiated. A dose of 20 Gy in five fractions has been shown to be as effective as any of the more protracted fractionation schemes.

Solitary metastases should be considered differently in an otherwise fit patient, especially if originating from a primary with 'good prognosis' histology. Here, tumour resection, where possible, is the treatment of choice. The growth pattern of brain metastases often allows complete macroscopic removal to be achieved. Post-operatively, whole-brain radiotherapy is given (20 Gy in 5 fractions or 30 Gy in 10 fractions) with or without a local boost. An alternative approach is to offer stereotactic radiosurgery (20 Gy in a single fraction), again with whole-brain radiotherapy to follow. Although it is conventionally given, the value of additional whole-brain treatment is not determined.

Chemotherapy can be useful in patients with brain metastases from chemo-sensitive primaries. It should be used as first-line therapy (or following resection) in germ cell tumours or as an alternative to radiation in small cell lung cancer and lymphoma. It can also be used as second-line treatment in less chemo-sensitive tumours such as breast cancer. The disruption of the blood-brain barrier by the tumour means that agents normally used to treat systemic metastases in these diseases may be tried, with response in about 30%.

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