Brain Tumours

Brain or spinal cord tumours (CNS tumours) can arise from the brain, spinal cord and the skull and are referred to as primary brain tumours.

Cancers from elsewhere in the body can also spread to the brain and spinal column and are referred to as secondary or metastatic tumours. Examples are lung cancer, breast cancer, prostate cancer and melanoma.

Primary CNS tumours can be classified into benign (slow growing and not life threatening) or malignant (life threatening).

In broad terms primary tumours can arise from the neural tissue or meninges (membrane around the brain and spinal cord). Tumours can arise from any part of the brain and spinal cord.

The most common malignant CNS tumours are:

1. Astrocytomas
2. Oligoastrocytomas
3. Ependymoma

The most common benign CNS tumours are:

1. Meningioma
2. Pituitary adenoma
3. Schwannoma

Brain tumours become symptomatic when it occupies space in the brain and exerts mass effect on the brain. Common symptoms would be headache, nausea and vomiting. Depending on the site of the tumour it can cause limb weakness, facial paralysis, seizures, visual loss and balance disturbances. The symptoms are often confused with a stroke and only after performing a CT or MRI scan is the tumour diagnosed.

The investigation of choice is a contrasted MRI scan.

Spinal cord tumours usually present with limb weakness or severe back pain.

Treatment of spinal cord tumours can be either with surgery and/ or radiotherapy.

Primary benign brain umous can usually be cured with surgery alone provided the entire tumour is removed.

Primary malignant brain tumours can usually be partially removed with surgery. Radiotherapy and chemotherapy can then be used to further control tumour growth. Unfortunately for high grade malignant brain tumours the prognosis remains poor and can not be cured.

Spinal cord and tumours involving the vertebra can be removed via a laminectomy or removal of the entire vertebra . This is usually accompanied by a mechanical stabilization to prevent collapse of the vertebra and spinal cord damage.

Radiosurgery is a form of focused radiotherapy and is the treatment of choice for small benign tumours. The advantage of this modality is that it can avoid surgery and shrink the tumour. This is a single session treatment over one day and the patient can be functional the next day, avoiding the risks of open brain surgery. Tumours normally treated with this method are acoustic neuromas.