Brain tumor refers to formation of abnormal cells within the brain. There are two main types of brain tumors: cancerous (malignant) tumors and indolent (benign) tumors. Presentation may include headaches, seizures, problem with vision, vomiting, decreasing sensorium and mental changes. The headache is classically worst in the morning and relieved with vomiting. More specific problems may include difficulty in walking or speaking.
Majority of brain tumors don’t have any specific causative factors. The best known environmental risk factor for brain tumors is radiation exposure. Impaired immune systems have an increased risk of developing lymphomas (cancers of lymphocytes ). In rare cases (5%) brain cancers run in families.
Environmental factors such as exposure to solvents, pesticides, oil products, rubber, or vinyl chloride (a chemical used to manufacture plastics), petroleum products, and certain other chemicals have been linked with an increased risk of brain tumors. Exposure to aspartame (a sugar substitute) and infection with certain viruses (Epstein Barr virus, human cytomegalovirus, polyoma virus) are possible risk factors. Relation to cellphone use, head injury, power lines, diet, smoking and alcohol remains controversial.
1. Headache occurring in later onset of life and gradually increasing in intensity. There can be a constant aching pain without any pain-free period in between. Usually headache will be maximum in the morning and the victim will wake up with severe headache.
2. Projectile vomiting mostly in the morning. Here the vomiting will not be preceded by nausea. Vomiting offers temporary relief from the headache.
3. New onset seizures can be focal seizures (more significant) involving only part of the body or it can be generalized seizures.
4. Weakness or numbness- progressively increasing and can involve only one limb or one side of the body.
5. Visual problems especially when it involves the optic nerve (nerve of vision) or pituitary gland.
6. Cognitive problems occurring suddenly like memory problems, behavioral changes, language problems, confusions etc
7. Difficulty in speech when tumor involves the speech area
8. Gait disturbances, imbalance, in coordination or weakness of facial muscles
9. Rapid personality changes
Tumors like meningiomas, certain gliomas, pituitary adenomas, nerve sheath tumors, germ cell tumors, haemangioblastomas, cavernomas, and certain lymphomas are curable.
Survival rates in brain tumors depend on the type of tumor, size, area involved and early detection, age and health of the patient.
Extent of surgical tumor removal
The primary and most desired course of action is surgical removal (resection) via craniotomy. Minimally invasive techniques is the trend in neurosurgery. Endoscopic surgeries are also being done. With the availability of ultramodern operating microscopes, neuronavigation systems, cavitron ultra sonic aspirator, endoscopes, sophisticated drills, intraoperative MRIs and other sophisticated equipments along with better understanding of surgical techniques, the safety and success rate for brain tumor surgery has dramatically improved.
Radiotherapy is the most commonly used treatment for brain tumors. Radiosurgery is a treatment method that uses computerized calculations to focus radiation at the site of the tumor while minimizing the radiation dose to the surrounding brain. Types of stereotactic radiosurgery, include gamma knife, linear accelerator and cyberknife.
Chemotherapy: is a treatment option for cancer, and can improve survival in 20% brain cancers.
Role of pharmacological therapy is limited except for anti epileptics (controlling fits) and steroids(reduce brain oedema)
Extensive research and studies are going on for better understanding of the behavior of different brain tumors and more and more treatment modalities are being tried to fight this disease. Immunotherapy/ biological response modifier (BRM) therapy, oncolytic virus therapy. Targeted therapy of faulty genes or proteins, gene therapy. Hormonal therapy, photodynamic therapy and electric field therapy are some of the treatment modalities that may bring hope in the future.
(The author is a consultant nurosurgen in VPS Lakeshore Global Lifecare Hospital, Kochi,)