Brain tumors may start in the brain (primary tumors) or they may start elsewhere in the body and be carried to the brain in the blood (secondary tumors). Secondary brain tumors are more common, only about 10% of brain tumors actually start in the brain.
Primary brain tumors may arise from several different kinds of tissue. The actual brain nerve cells themselves rarely form tumors.
What are the most common type of brain tumor?
The main kinds of tumors in the brain are:
- Meningioma (benign tumors of the membranes that form the brain coverings)
- Glioma (tumors of the glial tissue, the tissue that binds the nerve cells and fibers together)
- Hemangioma (tumors of the brain’s blood vessels). These can cause seizures and partial paralysis.
- Pituitary adenoma (tumors of the pituitary glands). These can sometimes cause Cushing’s syndrome and other complications.
Some brain tumors are benign. Benign tumors are those that never seed off to other parts of the body and always remain at the site of origin. In this situation, however, “benign” may be a misleading term.
Because the brain is enclosed in a rigid bone casing, anything growing inside is very likely to do harm by pressing on brain structures. However, if diagnosed early enough, benign tumors are often easier to remove.
Symptoms of brain tumor
The signs and symptoms of a growing tumor within the skull are mainly caused by a progressive rise in the internal pressure, either from the growing mass itself or from its interference with the normal circulation of the cerebrospinal fluid, which surrounds and permeates the brain.
The tumor itself causes pressure inside the skull, which causes the symptoms. These include:
- Changes in mental function that may be subtle.
- They may include irritability, lethargy, indifference, apathy, forgetfulness, lack of insight, or drowsiness
- Severe, persistent headache
- Vomiting, which is sometimes sudden and for no apparent reason.
- Dizziness, either major seizures or local twitching
- Loss of part of the field of vision or loss of hearing
- Personality changes
- Abnormal and uncharacteristic behavior.
It is important to see a doctor if you start to have new, persistent and severe headache, without any obvious cause, especially if it is associated with sudden unexpected vomiting.
Causes of brain tumor
Some brain tumors are congenital (present at birth) and are due to abnormal development before birth. The cause of non-congenital cancers is not fully understood.
There has been some publicity in the media about a possible connection between brain tumors and radiation from mobile phones. However, this is far from proven.
How brain tumor can be diagnosed?
The diagnosis is made on the basis of the symptoms and the findings on special forms of scanning such as computerized tomography scan (CT scan) or magnetic resonance imaging (MRI scan). Both can show the brain itself rather than just the bone which surrounds it.
Examination by your GP of the back of your eye using an instrument called an ophthalmoscope, may show changes caused by raised pressure inside the skull due to the presence of a tumor. However, A rise in the pressure in the skull does not necessarily indicate tumor.
Brain tumor treating options
Treatment is by surgical removal, and often also with radiotherapy. There have been major advances in these areas. Some tumors once thought of as inoperable now respond well to modern treatment.
What are the complications of brain tumor?
The outcome depends on the location, type and degree of malignancy of the tumor. (‘Degree of malignancy’ means the speed with which it grows and spreads to other areas.) Many common brain tumors are not malignant.