Brain Tumors
Date:
03/01/2011
Brain tumors are mass formations developing inside the skull. Tumors develop if the body fails to control any kind of cell activity and cell division is out of control. Patients diagnosed to have a tumor usually come across two terms: benign and malign. Benign brain tumors consist of benign cells. They have distinct borders and generally do not recur after surgical removal.
Malignant brain tumours are life threatening. These cells not only damage surrounding tissue but also present the risk of recurrence. Malignant cells developing in other parts of the body can proliferate to other areas, however brain tumors are generally contained in the area they originally appear even if they are malignant. On the other hand, benign tumors developing in life threatening parts of the brain may be considered malignant although the cells that form it are technically benign. Although malignant brain tumours on cellular terms may never spread to other parts of the body, there is a possibility of them reaching distant parts of the brain and spinal cord.
The skull is a bony structure and contains no mobile joints. When a tumor develops inside the skull it causes compression on the brain since it has no place to expand. The symptoms and findings differ tremendously depending on the characteristics of the area compressed by the tumour. Symptoms and findings are directly linked to the area affected. Sometimes tumours inhibit the circulation of spinal fluid within the ventricles of the brain causing them to swell. This usually causes a rise in pressure within the skull. Another outcome of tumours can be fluid accumulation, otherwise known as oedema. The sum of effects caused by tumour compression, increase in pressure and the resulting development of oedema is termed tumour mass index.
Tumours originating from brains cells are referred as “primary brain tumours”. Tumours developing in other parts of the body which later spread (metastasis) to the brain are termed “metastatic brain tumours”.
How are brain tumours diagnosed ?
Diagnosing brain tumours commonly start with patients seeking medical attention in response to a number of different complaints. A specialist physician will listen to the patient’s story in detail and then perform a neurological examination. Physicians will attempt to make a diagnosis with various tests and investigations should a tumour be suspected.
The skull hides the brain and the tumour inside it. Physicians are unable to see or feel the tumour during regular patient examination. Based on the symptoms and findings the tumour presents, physicians will make an assumption on the presence of a mass inside the skull. Various screening methods are employed to detect brain tumours.
The most common methods include:
1. CT (Computed Tomography),
2. MRI (Magnetic Resonance Imaging),
3. PET Scan (Positron Emission Tomography),
4. DSA (Angiography), and
5. SPECT (Single Photon Emission Computed Tomography)
Final diagnosis for the cell type in brain tumours is only possible after surgical removal and examination under a microscope. However, based on previous experiences a substantial guess can be made on the cell type by looking at the obtained images. The specialist examining the patient will try to make a diagnosis by using the symptoms as clues. Tumour symptoms and findings generally differ depending on size and the area affected.
Meanwhile, the tumour may expand its impact causing new symptoms and findings as it continues to grow. Besides the areas directly affected, tumours may present various other outcomes depending on the amount of pressure inside the head or the extent of oedema. Sometimes, symptoms and findings caused by the tumour are so slow to develop and it might take a long time before the diagnosis can be confirmed.
Pressure Increase Inside the head: Excessive tumour growth can cause pressure increase inside the head by compression on ventricles and thus inhibiting the circulation of spinal fluid. Pressure inside the head can rise due to expanding ventricles and as an outcome of tumour causing swelling in neighbouring tissues.
Symptoms: Initial symptom is usually only a headache. Patient will wake up with headaches, which usually recede during the day. Pain increases whilst lying down. Patient may wake up feeling nauseous and be compelled to vomit. Changes might be observed in mental abilities that may include a general state of fatigue and numbness. Movements may lack coordination and appear clumsy. Different types of epileptic fits may also develop.
How is it treated?
Treating brain tumours is very different than treating tumours in other parts of the body. Firstly we use very fine precision tools in the surgical treatment of brain tumours. Secondly, the blood inside the brain blocks the access of systemic medication. Thirdly, the methods used for treatment and the potential side effects are extremely complicated. These factors require brain tumour treatment performed by a very experienced team of medical specialists from a wide spectrum of disciplines. Patients and their families are provided detailed information on the patient’s current health condition, the purpose of treatment, potential side effects and anticipated changes in quality of life following treatment. The most common forms of treatment in brain tumours include surgical intervention, radiotherapy, chemotherapy and immunotherapy. A single or combination of treatment methods may be employed.
Surgery
This is the preferred form of treatment for accessible brain tumours. Some brain tumours are difficult to access. The majority of benign brain tumours however can be removed by surgery and adequate as treatment. Malignant brain tumours present the potential of spreading to neighbouring tissue and this is why their borders cannot be clearly defined. Having said that, removing most of the tumour by surgery increases life expectancy and the patient’s quality of life. The main objective of surgery is removing the tumour entirely wherever possible. If this is impossible, the next best option is to remove as much as possible. This helps improve patient’s symptoms, findings and quality of life, and increase life expectancy. More so, we increase the chances of the remaining small tumour giving better response to other forms of treatment. Another objective of surgery is to put a definite diagnosis to the condition. Using a number of marking techniques, pathology specialists are able to determine the type of cells by examining the removed mass under a microscope. Surgery also helps determine the exact size of the tumour. The surgeon is able to examine the mass entirely together with neighbouring tissue. This makes it possible to employ new treatment methods. There are cases where various radio-therapeutic implants are used during surgical intervention.
Radiotherapy
Most tumour cells are sensitive to radiation. Radiotherapy method involves exposing tumour to radiation without harming normal healthy tissue nearby. Radiation sources include X-ray generating linear accelerators and gamma rays generating Co60 sources. Today we have access to a number of different radiotherapy methods. Popular methods include traditional radiotherapy, inner cell radiotherapy and stereotactic radiosurgery (Gammaknife and Cyberknife).
Chemotherapy
This method involves the use of special medication designed to eradicate tumour cells. Chemotherapy may be applied before or after surgery or radiotherapy. Tumour type defines the variant, dose and combination of chemotherapy medication. Chemotherapy demands the cooperation of an experienced oncologist and brain surgeon.