Survival depends on many different factors. It depends on your individual condition, type of cancer, treatment and level of fitness. So, no one can tell you exactly how long you will live. Brain tumours are quite rare. And there are many different types. Survival depends on what type of tumour you have. Some types are very rare and it can be difficult to find survival statistics for all of the types.
Type of tumour
Different types of brain tumours respond differently to treatment. Some respond better to radiotherapy than others, for example. Some types are likely to spread (infiltrate) into the surrounding brain tissue. This may make them impossible to remove with surgery.
Grade of the tumour cells
Grade is one of the most important factors for some types of tumours. But for others the grade is much less likely to predict how the tumour will respond to treatment. Generally, fast growing tumours are much more likely to come back after treatment than slow growing tumours.
Position in the brain
The position of the tumour in the brain may affect the type of treatment that doctors can give. For example, surgery is a main treatment for most types of brain tumour. But some parts of the brain are more difficult to operate on than others. Sometimes the tumour may be in an area where it is not possible to remove it all with a safety margin of healthy tissue around it. This may increase the risk of the cancer coming back.
In some areas of the brain it is not possible to operate at all. These include the nerves that control your sight (optic nerves) or the brain stem, spinal cord, or areas close to or surrounding major blood vessels. For tumours in these areas, radiotherapy or chemotherapy may be better options for treatment. The outlook will then depend on how well the tumour responds to those treatments.
Size or shape of the brain tumour
Large tumours or those where the edge of the tumour is not clear may be more difficult to remove.
Reference:
http://www.cancerresearchuk.org/about-cancer/brain-tumours/survival