Brain cancers can be divided into two groups: primary and secondary.

Primary brain cancers are those which actually start within the brain. There are a number of different types of primary brain cancers (these are classified according to the type of tissue in which the tumour originated).

Secondary brain tumours are tumours which have started from a primary cancer somewhere else in the body which has then sent seedlings of tumour (or metastases) through the blood stream to the brain. Secondary tumours in the brain have the same appearance under the microscope and behave similarly to the primary cancer from which they came. For example, if a lung cancer forms secondaries in the brain, those secondaries will look and behave like the lung cancer and not like a primary brain tumour.

Temodal (the trade name of a type of chemotherapy called temozolomide) is a new drug which has been shown to have some effect against the most common type of primary brain tumour which is called an astrocytoma. It is used for more advanced tumours where surgery or radiotherapy is not possible. Temodal benefits around 25 to 30% of patients who respond to treatment with some shrinkage of the cancer and a possible increase in life-expectancy of a few months. Temodal does not help in the control of secondary brain tumours. The treatment of secondary brain tumours relies on either surgery, radiotherapy, steroids or different chemotherapy drugs (or a combination of one or more of these).

The precise choice of treatment depends on the primary cancer from which the secondary tumour has come from as well as the position and number of brain secondaries.