A brain tumour is an abnormal growth of cells within the brain. Brain tumours can be either benign (non- cancerous) or malignant (cancerous). Benign brain tumours does not contain cancerous cells, do not spread to other tissues and usually, once removed rarely they do recur. Malignant brain tumours are cancerous in origin that may invade and spread to surrounding tissues, grow rapidly. Tumours that arise within the brain tissue are called as primary brain tumours. Tumours that spread to the brain through bloodstream from other parts such as the breast or lung are called secondary or metastatic brain tumours.
The exact cause of brain tumours is not known, but certain risk factors such as exposure to radiation, genetic factor, HIV infection and smoking may increase the risk of developing a brain tumour.
Patients with brain tumours may experience headache, vomiting, weakness, seizures, drowsiness, difficulty in walking, personality changes, slurred speech, and visual changes. Certain symptoms occur when a tumour presses on the other parts of the brain.
Doctors group brain tumours by grade. The grade of a tumour refers to the way the cells look under a microscope:
Brain tumours in adults are different from that of the children. Some of the common adult and child brain tumours.
Among children, the most common types of brain tumours are:
Among adults, the most common types are:
Depending upon the type, location, grade and size of the tumour, age and health condition of the patient, tumour may be treated by surgery, radiation therapy, or chemotherapy. Often combination of one or more options may be recommended.
Surgery is the preferred treatment for most brain tumours. The most common types of surgery performed for brain tumours include:
Biopsy: Biopsy is often used for diagnostic purpose where a sample of tissue is removed for a detailed analysis. However it can also be used as a treatment option in certain cases such as removal the tumour growth. An MRI brain scan or CT scan may be done to locate the tumour. Biopsy can be performed under general anaesthesia where a small hole called burr hole will be drilled to insert the biopsy needle and the tumour will be excised. The tumour sample can be used for further analysis.
In cases of tumours deep within the brain special technique called guided biopsy will be performed. Guided biopsy can be performed by two different techniques stereotactic biopsy or neuronavigation. In stereotactic biopsy technique, a specially designed head frame is fitted either before or after scanning. The scans show both the location of tumour and the frame. This helps in tracing the exact distance of tumour from reference point on the frame so that the biopsy needle can be guided precisely to the target area. Under local or general anaesthesia, your surgeon will drill a very small hole in the skull and the head frame will guide the biopsy needle to remove the tumour or tissue sample.
For neuronavigation, biopsy is taken with a fine needle in much the same way as the stereotactic biopsy, but without using a head frame. You may have markers stuck to your head called fiduciary markers before you have the scan. These markers can be seen on the scan which help guide the needle into the right position.
Craniotomy: It is a surgical removal of portion of the skull bone to expose the brain. Craniotomy is usually done under general anaesthesia. However it can also be done under local anaesthesia where the patient is awake during part of the surgery. This procedure is called awake craniotomy and is done to check for brain functioning during surgery. In craniotomy procedure, an incision is made through the skin and a piece of bone is removed to expose the area of brain over the tumour. After removing the brain tumour the piece of bone is replaced and the flap of the scalp is stitched over it. Craniectomy is a technique for tumour removal, similar to craniotomy but the bone flap will not be replaced after the surgery.
If a tumour cannot be completely removed, only part of the tumour is removed and the procedure is called partial resection or debulking.
After the surgery you will be closely monitored for the first 12 hours and a tube is placed at the site of the operation to drain the excess blood from the head. Swelling and bruising of the face and eyes may occur that may resolve within few days. Some patients may experience headache and pain medications may be recommended to relieve the pain
In some cases where tumours block the flow of cerebrospinal fluid (CSF) and increases the intracranial pressure, shunting is performed to drain the excess of CSF. The shunt is a thin long tube placed in brain and advanced to other body part such as abdomen where excess of CSF will be drained and reabsorbed by the body.