Is Brain Tumor A Type Of Cancer?
There is a general misconception about brain tumors and brain cancer being the same thing. Even though they are related, it is important to understand the types of brain tumor and at what particular stage does it turn cancerous.
Our body is comprised of millions of cells where each cell performs requisite functions. Certain cells multiply by diving to form new cells to keep the body functioning. When these cells lose the control of multiplication they divide in any order and at any rate. The extra cells form a mass or lump of tissues which is not required in the body and is called a tumor.
Brain Tumor Type:
Benign brain tumors are those that can be removed and are not likely to reoccur. They do not contain cancer cells and do not invade adjacent tissues. They can exert pressure on the veins and nerves that come in their path and cause the symptoms.
Malignant brain tumors are cancerous reoccurring tumors. They are fatal as they grow rapidly and their roots spread into adjacent healthy tissues and organs. Malignant tumor without roots is compact and said to be encapsulated.
Primary Brain Tumor
Originating from the brain, the primary tumor can be benign or malignant. Usually, the primary tumor starts in the cerebrum, which is the main part of the brain. Some tumors can start in the meninges, a thin membrane around the brain and spinal cord. A tumor can also begin growing in the glands associated with the brain, i.e. the pituitary gland or the pineal gland.
Gliomas: Primary malignant brain tumor originates in the brain and the cells can spread within the brain and reach up to the spine. They rarely spread to other parts of the body. Approx 80% of malignant primary brain tumors are collectively known as gliomas. These originate in the glial cells which form the basis of the connective tissues of our central nervous system.
Depending on the range or degree of malignancy, the gliomas are classified into four grades:
- Grades I and II are considered low-grade tumors that grow at a slow rate and are least malignant. Grade I is actually the borderline stage between benign and malignancy.
- Grades III and IV reflect high-grade. Grade III tumors are malignant and seem to grow at a moderate rate. Grade IV tumors, like the glioblastoma multiforme, are the most malignant primary tumors and also the fastest-growing.
Depending on the location of the tumor, the gliomas are described as:
- Gliomas developing in the lowest part of the brain are termed as brain stem gliomas and around 20% of tumors in children fall in this category. The brain stem connects the cerebrum to the spinal cord.
- Tumors that form in the cerebellum are termed as cerebellar astrocytoma. The cerebellum is a crucial part of the brain that controls body balance and coordination.
- Optic gliomas grow in the optic nerve and parts of the eye. It is observed to affect children younger than age 10.
Survival from primary brain tumors and the outcome of the treatment depends on the type of tumor, its location, size, and extent of its growth.
It also depends on the patient’s age, their ability to function and also if there are any other illnesses that can complicate the treatment, like diabetes.
Secondary Brain Tumor
It is a cancerous tumor that originates in any part of the body and the cancer cells spread to the brain. It is also known as a metastatic brain tumor. Cancer cells in the tumor break away from the primary tumor and travel through the bloodstream across the body. These cells can lodge in the brain and grow into new tumors. Cells from cancer of the lung, breast, kidney, stomach, bowel, and skin can reach the brain.
This is a more complicated form of brain tumor because here the origin of the tumor needs to be traced because the treatment depends on the correct identification of the primary cells. If the origin of cancer was in the kidney, then the cancer cells the brain are actually the kidney cells. In the case of primary brain tumors, the cancerous cells are brain cells.
Survival from secondary brain tumors cannot be accurately predicted because if the cells reached the brain, they could have reached other parts and begin shooting cancerous growths there. The complications increase and it is difficult to predict the outcome of treatment.