What is a Brain Tumor?
Tumors of the brain are the most commonly occurring solid tumors in children. Each year in the United States approximately 2,900 children are diagnosed with a brain tumor. Most of these tumors arise from the cells of the brain. A tumor is technically a mass or lump, typically consisting of abnormal tissue that should not be there.
A slow-growing (benign) tumor does not contain cancer cells and usually, once removed, does not recur. Most benign brain tumors have clear borders, meaning they do not invade surrounding tissue. These tumors can, however, cause symptoms similar to cancerous tumors because of their size and location in the brain.
Fast-growing (malignant) brain tumors are more aggressive and invade surrounding tissue. They may spread throughout the cerebrospinal fluid space surrounding the brain and spinal cord. These type of brain tumors very rarely spread to other areas of the body outside of the central nervous system, but may recur after treatment.
Brain tumors can occur at any age. Brain tumors that occur in infants and children are very different from adult brain tumors, in terms of both the type of cells and the responsiveness to treatment.
Anatomy of the brain:
The central nervous system (CNS) consists of the brain and spinal cord. The brain is an important organ that controls thought, memory, emotion, touch, motor skills, vision, respirations, temperature, hunger and every process that regulates our body.
The brain can be divided into the cerebrum, the brain stem and the cerebellum:
Cerebrum (supratentorial, or front of brain)—composed of the right and left hemispheres, with each having a frontal, temporal, parietal and occipital lobes. Functions of the cerebrum include: initiation of movement, coordination of movement, temperature, touch, vision, hearing, judgment, reasoning, problem solving, emotions and learning.
Brain stem (midline, infratentorial)—includes the midbrain, the pons and the medulla. Functions of this area include: movement of the eyes and mouth, relaying sensory messages (i.e., hot, pain, loud), hunger, respirations, consciousness, cardiac function, body temperature, involuntary muscle movements, sneezing, coughing, vomiting and swallowing.
Cerebellum (infratentorial, or back of brain)—located at the back of the head, its function is to coordinate voluntary muscle movements and to maintain posture, balance and equilibrium.
For a more thorough discussion of the anatomy of the nervous system, follow this link.