A brain cancer is a tumor or abnormal growth of cells within the brain tissue itself. This abnormal growth of cells can be of two types, those which arise and grow from the brain tissue itself, and are called primary brain tumors, and those which arise elsewhere in the body and travel/ metastasize to the brain, mostly through the bloodstream, and these are called secondary brain tumors. Primary brain tumors very rarely spread to other parts of the body and almost all brain tumors remain confined to the brain tissue.
There are about 40 different types of brain tumors known to us, depending on the tissue they arise from, the part of the brain they are present in and so on. But all of them can be easily divided into two categories:
- Benign tumors – are growths which are made up of cells that grow slowly and these tumors do not invade other tissues, be it adjacent or distant. Common examples of benign brain tumors include meningioma, craniopharyngioma, pituitary tumors and neuroma.
- Malignant tumors – are growths which are made up of cells that grow rapidly and invade adjacent brain tissue and can even spread to the spinal cord. Common examples of malignant brain tumors include glioblastoma, mixed glioma, oligodendroglioma and astrocytoma.
Brain cancers make up about 1.4% of all cancers that people can develop each year, with the incidence being 23,770 new cases of brain cancer being diagnosed each year around the world. The five year survival rate for brain cancer has come up to an improved value of 22%, with all the advancements in medicine and technology.
What Are the Symptoms of brain Cancer?
- Headache – is by far the commonest and earliest symptom which indicates the presence of a brain tumor. Even though all headaches do not indicate a brain tumor, if it becomes persistent, increases in severity or is present on waking up, you need to make sure you see a doctor.
- Paralysis or weakness of the muscles which is mostly evident on one side of the body than the other.
- Difficulty in walking and maintaining balance as well as performing coordinatedmovements.
- Nausea and vomiting, especially if it occurs early in the morning along with dizziness or vertigo
- Impaired speech with changes in voice, as well remembering words.
- Impaired vision including blurring of vision or double vision.
- Impaired sense of smell and taste.
- Presence of seizures, which can be full blown convulsions or mild events such as twitching of muscles or transient loss of awareness.
- Altered level of consciousness with periods of increased drowsiness or loss of consciousness.
- Change in personality of an individual with increased irritability.
What causes brain cancer?
As with cancers in other parts of the body, an exact cause for the development of brain cancer cannot be pointed out. But certain factors have been associated with an increased risk of developing brain cancer. These include:
- Hereditary – people with a certain genetic predisposition have been known to be at increased risk.
- Individuals who have been exposed to high levels of radiation to the head.
- Cigarette smoking.
- HIV infection.
What tests are used to diagnose brain cancer?
Brain cancers are diagnosed by doctors using a physical examination and various investigation. The doctor will carry out a neurological examination to check the functioning of various parts of your brain and try and pinpoint where exactly the problem lies. Your muscle power, the presence or absence of reflexes, your balance, ability to distinguish between hot and cold temperatures, as well as the ability to feel a pin prick sensation in various parts of your body will all be tested. Your doctor will also try and check for increased pressure inside your cranial cavity due to the tumor, by checking if your optic nerve is bulging, using an ophthalmoscope. Although the findings of a neurological examination are significant to pinpoint a problem, a confirmation of the diagnosis is made following investigations which include:
- MRI or CT scan of the brain
- PET scan
- Single Photon Emission CT scan
- Magnetic Resonance Spectroscopy
- Lumbar Puncture which is also called a spinal tap
Depending on the findings of the examination and the investigations, your doctor will be able to stage the brain cancer. Staging of a cancer gives you an idea of the extent of the cancer, the size of it and how far into the brain tissue it has spread. Brain cancers are also graded according to the type of cell present in the growth. They are graded into 4 groups according to how rapidly the cells can grow and their ability to invade adjacent tissue. Grade 1 has cells which look almost normal and grow very slowly. Grade 2, the cells are less normal than in grade 1 but they also grow slowly and therefore Grade 1 and Grade 2 tumors are called low grade tumors. Grade 3, the cells look distinctly abnormal and are actively growing. Grade 4, the cells look very much abnormal and are growing at a rapid rate.
What is the treatment for brain cancer?
Treatment of brain cancer cannot be standardized, and has to be individualized according to each patient. Therefore you need a specialized team of professionals to care for a patient diagnosed with brain cancer and this includes a GP, Neurologist, Neurosurgeon, Medical Oncologist, Radiation Oncologist, Cancer Nurses, as well as other healthcare workers such as dietician, speech and occupational therapists and social worker.
Surgery, Chemotherapy, Radiotherapy and Steroid Therapy are the mainstay of treatment modalities available for the treatment of brain cancer. And most of the time, the individualized care a patient gets will include a combination of these treatments.
Some types of brain tumors can be completely removed using surgery, whereas for others you can use post-operative radiotherapy to gain better control of the growth of the cancer and improve the survival. With tumors which cannot be operated on, the goals of treatment is to reduce the symptoms, by controlling the growth, shrinking the tumor and reducing the swelling of the brain tissue around it, using radiotherapy.
Palliative care is aimed at symptom relief and slowing down the spread of the cancer, when nothing else can be done to completely cure the condition. Keeping the patient as comfortable as possible with pain relief is an important factor. Palliative care also makes use of chemotherapy, radiotherapy and various other drugs to achieve this.
What is the Prognosis of brain cancer?
Prognosis means the outcome of a disease, and in the case of brain cancer the outcome is dependent on many factors. The stage and grade of the cancer, as well the general health condition of the patient all play a role in deciding if the outcome is going to be poor or not. In the case of a benign brain tumor cure is highly likely because it can be completely removed through surgery. But in the case of a malignant tumor, the outcome depends on how early the diagnosis has been made, and how well the tumor responds to the treatment given.
Screening for and prevention of brain cancer
There are no screening methods available for the early diagnosis of brain cancer currently, and there have not been any well known methodsof preventing the development of brain cancer as well.