Brain cancer is caused by a mass of abnormally growing malignant cells (tumor) present in the brain or skull. Tumors are formed when the orderly process of cell growth and replacement is disordered. Cancer cells do not mature normally and do not perform their normal functions. Over time these cells form a mass. Tumors in the brain may either be benign or malignant. Irrespective of the type of tumor, they pose a threat to life owing to their location.
Malignant tumors grow and spread rapidly, thereby, overpowering healthy brain cells and starving them of blood and nutrients. The brain is the control center for the vital functions of the body and is affected by the cancerous growth. This affects all vital functions like speech, vision, movements, hearing and more. Brain cancer is of two types: one that originates from a brain cell and grows without spreading to other organs, referred to as primary brain cancer; the second one is that in which the malignancy has started elsewhere and moved to the brain through the blood stream, referred to as metastatic brain cancer.
Types and grades of brain cancer
Primary brain cancer: This type of cancer develops in the brain and does not spread to other parts. The most common types of primary brain tumors are gliomas, meningiomas, pituitary adenomas, primitive neuroectodermal tumors and vestibular schwannomas. The names are based on where the tumor is located in the brain.
Metastatic brain cancer: These brain tumors originate in other parts of the body like lung, breast, colon, and skin, and move to the brain through the blood stream. These are among the most common cancers that spread to the brain.
The grading of tumors is made based on their abnormality. The treatment of brain cancer is based on the grade of the cancer. The speed at which the cancer grows and spreads depends on the grade.
- Grade 1 – Cells appear nearly normal and exhibit slow growth. Long term survival of the patient is possible.
- Grade 2 – The cells look slightly abnormal and grow slowly. There is a likelihood of spreading of the tumor and recurrence at a later stage.
- Grade 3 – The cells appear abnormal and growth is rapid. The cancer is growing and spreading to surrounding tissues and chances of recurrence is high.
- Grade 4 – The cells appear abnormal and exhibit rapid growth and spread quickly.
There is a likelihood for a tumor to change, for instance, benign becomes malignant or lower-grade changes to a high-grade cancer.
Causes of brain cancer
Determining the exact cause of brain cancer is difficult. There are a few likely causes of brain cancer: radiation to the head, heredity, HIV infection and smoking. Exposure to environmental toxins could also cause brain cancer.
Signs and symptoms
The symptoms and signs of brain cancer depend on the location of the tumor. Development of the symptoms happens gradually, making it difficult to even notice the growth of cancer. Common symptoms of brain cancer include:
- Headache
- Muscle weakness
- Parasthesias
- Fatigue
- Difficulty in walking, hearing or vision
- Seizures
These symptoms may be caused by some other ailment, further detailed diagnosis helps in confirming brain cancer.
According to statistics, as many as 80,000 brain tumors are diagnosed every year in the country. 1/3 of these cases are cancerous tumors. Brain cancer can affect anyone at any age. Brain cancer is the leading cause of cancer-related deaths in patients under the age of 35 years.
