Overview

What Are Tumors of the Brain?

Brain tumors are a mass of abnormal cells in your brain. The tumor may be primary (starting in the brain) or cancer may have spread to the brain (metastatic). All brain tumors are either benign (slow-growing, not cancerous) or malignant (growing quickly, cancerous). Brain tumors can cause serious damage, even if they are benign. The degree of damage depends upon the type, size and location of the tumor.

Types of brain tumors

More than 100 types of brain tumors have been identified and are usually named by the type of brain cell or part of the brain where they begin to grow. More common types of primary brain tumors include:

• Astrocytoma: This is the most common type of malignant brain tumor, which can grow anywhere in the brain. It gets its name from the star-shaped brain cells that make up the tumor. Astrocytoma is common in all ages, however it is less likely to be malignant in children.
• Glioblastoma: This is a complex type of cancerous tumor that forms in the brain and spinal cord. It can occur in any lobe of the brain, but is most often found in the temporal and frontal lobe.
• Meningioma: This is the most common type of benign brain tumor and makes up about one-third of all primary brain tumors. It starts in the lining that covers your brain. In rare cases, this type of tumor can become malignant.
• Oligodendroglioma: This brain tumors forms in the cells that make the lining that covers nerves, called myelin. This type of tumor is usually malignant.

Adults are more likely to have a metastatic brain tumors. The most common cancers that spread to the brain are lung, breast, colon, kidney and melanoma skin cancers.

Primary brain tumors in children

Some primary brain tumors are found more commonly in children, including:

• Medulloblastoma: This tumor type is malignant and forms in the back part of the brain called the cerebellum, which is near the spinal cord. It can spread to the spinal cord and cause spinal fluid to back up into the brain.
• Ependymoma: This tumor, which is seen in young children and young adults, can range from benign to malignant. An ependymoma forms in the lining around fluid-filled areas of the brain.
• Brain stem glioma: This tumor can be benign or malignant and occurs in the base of the brain.