The central nervous system (CNS) is made up of the brain and spinal cord. When cells in the brain or spinal cord begin the multiply uncontrollably forming a mass, it is called a tumor.
Tumors can be benign or malignant. Benign tumors do not grow as rapidly as malignant tumors and do not invade surrounding tissue. Malignant tumor (called cancerous) grow more quickly and can migrate to surrounding tissue and other organs of the body.
The CNS controls movement throughout the body as well as transmitting sensory signals from the body to the brain. Therefore, CNS tumors are dangerous because the spaces are so small that any growth can affect the functioning of the nervous system tissues around it, causing loss of motor control and sensory input.
They are many types of CNS tumors, but common symptoms may include seizures, speech problems, mood and personality changes, weakness or paralysis, and loss of vision, hearing, and other senses. Symptoms will vary according to the location of the tumor along the nervous system.