• Ionising radiation.
• Vinyl chloride is associated with high-grade gliomas.
• Immunosuppression (eg.as a result of AIDS) may cause cerebral lymphoma.
• Inherited syndromes with an increased risk of brain tumours include neurofibromatosis, von Hippel-Lindau disease, tuberous sclerosis, Li-Fraumeni syndrome, Cowden's disease, Turcot's syndrome and naevoid basal cell carcinoma syndrome (Gorlin's syndrome).

Anyone presenting with new, unexplained headaches or neurological symptoms needs a thorough neurological study of history and examination.

The presentation will depend on location and rate of growth but includes features of a space-occupying lesion and raised intracranial pressure (ICP)

• Headache, which is typically worse in the mornings.
• Nausea and vomiting.
• Seizures.
• Progressive focal neurological deficits – eg. diplopia associated with a cranial nerve defect, visual field defect, neurological deficits affecting the upper and/or lower limb.
• Cognitive or behavioural symptoms.
• Symptoms relating to location of mass – eg. frontal lobe lesions associated with personality changes, disinhibition and parietal lobe lesions might be associated with dysarthria.
• Papilloedema (absence of papilloedema does not exclude a brain tumour).

• Diagnosis largely rests on brain imaging – eg. CT scan and/or MRI scan (with or without contrast). MRI is more sensitive.
• The spine may also need to be imaged, especially in CNS tumours that spread to the spine – eg. germ cell tumours and lymphoma
• Blood tests may be useful in determining any complications of the tumour (eg. bleeding disorders, hypercalcaemia or inappropriate antidiuretic hormone secretion) or in the initial assessment of other possible causes of headache
• Technetium brain scan: is useful in the diagnosis of skull vault (eg, metastases) and skull base lesions.
• Magnetic resonance angiography (MRA) and magnetic resonance spectroscopy (MRS) are occasionally used to define changing size or blood supply.
• Positron emission tomography (PET) is helpful in grading gliomas or locating an occult primary.
• Biopsy and tumour removal: stereotactic biopsy via a skull burr-hole to obtain histology of a suspected malignancy.
• Open exploration (craniotomy) may be required – eg. for a symptomatic meningioma.
• Lumbar puncture or CSF analysis is done in assessment of certain brain tumours

• Surgery
• Tumours should be resected whenever possible. Surgery will also provide tissue for a formal diagnosis.
• Surgery may not be a viable option, especially if the tumour is located in a region associated with critical function or where there is infiltration of local normal brain tissue.
• Surgery should also be considered to reduce mass effect and treat hydrocephalus in order to provide symptomatic relief.
• If surgery is not an option then radiotherapy should be considered.
• Radiation
• External beam radiotherapy can be curative for many patients and also prolongs survival.
• For some types of tumours, it is the treatment of choice – eg. metastatic brain tumours, leptomeningeal metastases.
• Whole brain radiation is used with some tumours – eg. medulloblastomas, primary CNS lymphomas. An alternative technique is 'involved-field radiation', which means that normal brain tissue is exposed to less radiation.
• In stereotactic radiosurgery, focal radiotherapy is administered to a target, thus avoiding exposure to normal brain tissue.
• Chemotherapy
• The role of chemotherapy in brain tumours is not as marked as in other tumours (except for CNS lymphoma, which requires aggressive intrathecal and intravenous chemotherapy).
• It does provide modest benefit and is important in palliative care and as an adjunct to combined surgery and radiotherapy.
• Commonly used agents include those that can cross the blood brain barrier - eg, temozolomide in glioblastoma multiforme, nitrosureas in oligodendrogliomas, platinum agents in medulloblastomas
• Other therapeutic agents
• Patients may also require analgesics, anticonvulsants, anticoagulants and corticosteroids.
• Corticosteroids help to reduce mass effect of raised ICP.

• Corticosteroids should be used if cerebral oedema is present.
• Surgery may be an option for patients with three or fewer brain metastases - provided the primary is controlled. This is associated with improved survival.
• For metastases that are larger in size, stereotactic radiosurgery may be an option.
• Whole-brain radiotherapy can be given after surgery or radiosurgery. However, it is currently debated whether it should be given early or late in the illness.
• Whole-brain radiotherapy is the only treatment modality for those who are not suitable for surgery or radiosurgery.
• Chemotherapy should be considered if the brain secondaries arise from a primary chemosensitive tumour.

All advanced neurological treatments including-

• Awake craniotomy for brain tumours
• Surgery for skull base tumours
• Surgery for CP angle tumours
• Lobectomy for localised tumours
• Radiotherapy for brain tumours (conventional/ 3D CRT/IMRT/ Stereotactic radiosurgery)
• Chemotherapy based on stage of cancers
• Metastatectomy for solitary brain oligometastasis