Brain Cancer is a disease where we see cancerous/malignant tumours in the brain. Some brain cancers happen when one type of cell alters its normal characteristics. The altered cells grow and multiply in abnormal ways. These being abnormal cells grow and become a mass or a tumour. Such brain tumours which originate in the brain are called Primary Brain Tumours. Tumours that do not invade nearby tissues or spread to other areas are called benign tumours, while the ones that do are malignant/cancerous tumours. Malignant tumours grow to form a mass of cancer tissue that interferes with brain functions such as muscle control, sensation, memory and other normal body functions. When the cancerous tumours spread from other body sites to the brain they are termed as Metastatic or Secondary Brain Tumours.
It is also important to note that while benign tumour is less serious than a malignant tumour, they can still cause many problems in the brain by pressing on nearby tissue. It is therefore advised that such benign tumours are monitored and/or treated as per doctors’ recommendations.
Symptoms of brain cancer usually develop over time and their characteristics depend on the location and size of the tumour. Brain cancer symptoms include:
- Behavioural and emotional changes
- Impaired judgment
- Impaired sense of smell
- Memory loss
- Paralysis on one side of the body
- Reduced mental capacity
- Inflammation of the optic nerve
- Impaired speech
- Inability to write
- Lack of recognition
- Spatial disorders
- Difficulty in speaking and swallowing
- Headache, especially in the morning
- Loss of hearing
- Muscle weakness on one side of the face
- Uncoordinated gait
- Mental and emotional changes
- Prolonged drowsiness (somnolence)
- Loss of vision
- Primary brain tumours may develop in different parts of the brain. The common types of primary brain tumours are Gliomas, Meningiomas, Pituitary Adenomas, Vestibular Schwannomas, and Primitive Neuroectodermal Tumours also called Medulloblastoma. Glioma also includes Glioblastoma, Astrocytoma, Oligodendroglioma, as well as Ependymoma.
Metastatic brain cancer is caused by the spread of cancer cells from a body organ to the brain. However, the causes for the alteration of normal cells to cancer cells in both metastatic and primary brain tumours are not yet fully understood. Research show that people with certain risk factors are more likely to develop brain cancer.
Individuals with risk factors, such as having a job in an oil refinery, handlers of jet fuel or chemicals like benzene, chemists, embalmers & rubber-industry workers, show higher rates of brain cancer than the general population. Some families have several members with brain cancer, however heredity/genetics as a cause for brain tumours has not been proven. Other risk factors such as smoking, radiation exposure and viral infections like HIV have been suggested but not proven to cause brain cancer. There is no evidence that brain cancer is contagious, caused by head trauma or caused by cell phone use.
The initial test is a medical interview and a physical examination of the person by the doctor. The findings of this will indicate whether there is a problem in the brain or the brain stem.
The most commonly used test for brain cancer detection is a CT scan. This diagnostic test resembles a series of X-rays and is not painful, although sometimes a dye needs to be injected into a vein for better images of some internal brain structures. Another test that is gaining popularity because of its high sensitivity for detecting anatomic changes in the brain is MRI (Magnetic Resonance Imaging). This test also resembles a series of X-rays and shows the brain structures in detail better than a CT scan. MRI is not as widely available as a CT scan.
People with brain cancer usually also have other medical problems; hence, routine lab tests may be done. These include blood tests, electrolytes and liver function.
If the tests show evidence (tumours or abnormalities in the brain tissue) of brain cancer, other doctors such as Neurosurgeons and Neurologists that specializes in treating brain ailments will be consulted to help determine how to treat the patient. Occasionally, a tissue sample (biopsy) may be obtained by surgery or insertion of a needle to help determine the diagnosis. Other tests may be suggested by the health-care practitioner to help determine the patient’s state of health or to detect other health problems.
A brain cancer treatment plan is customised for each patient. The treatment plan is constructed by the doctors who specialise in brain cancer, and treatments vary widely depending on the cancer type, tumour location, tumour size, patient age and patient’s general health status. A major part of the plan is also determined by the patient’s wishes. Patients should discuss treatment options with their healthcare providers. Most treatment plans for brain cancer are complex and can involve several consulting doctors.
Surgery, Radiation Therapy and Chemotherapy are the major treatment categories for most brain cancers. Individual treatment plans often include a combination of these treatments.
Surgery attempts to remove all of the tumour cells by cutting the tumour away from normal brain tissue. This surgery is often termed invasive surgery to distinguish it from non-invasive radiosurgery or radiation therapy described below.
Radiation Therapy attempts to destroy tumour cells in the brain by using high-energy radiation focused onto the tumour to destroy the tumour cells’ ability to function and replicate. Radiosurgery is a nonsurgical procedure that delivers a single high dose of precisely targeted radiation using highly focused gamma-ray or x-ray beams that converge on the specific area or areas of the brain where the tumour or other abnormality is located. This minimises the amount of radiation to healthy brain tissue. Equipment used to do radiosurgery varies in its radiation source; a gamma knife uses focused gamma rays whereas a linear accelerator uses photons and heavy-charged particle radiosurgery uses a proton beam.
Chemotherapy attempts to destroy tumour cells using chemicals (drugs) that are designed to destroy specific types of cancer cells. There are many chemical agents used. Specific drug therapies are numerous and each regimen is usually designed for the specific type of brain cancer and individualised for each patient. Chemotherapy can be administered intrathecally, by IV administration, and biodegradable chemically impregnated polymers. All treatments attempt to spare normal brain cells.
Other treatment options may include Hyperthermia (heat treatments), Immunotherapy (immune cells directed to kill certain cancer cell types) or steroids to reduce inflammation and brain swelling. These may be added to other treatment plans.