What is Medulloblastoma?
Medulloblastoma is a rapidly-growing tumor of the cerebellum — the lower, rear portion of the
brain. Also called the “posterior fossa,” this area controls balance, posture, and complex motor
functions such as speech and balance. Tumors located in the cerebellum are referred to as
“infratentorial” tumors. That means the tumor is located below the “tentorium,” a thick membrane that separates the larger, cerebral hemispheres of the brain from the cerebellum. In children, medulloblastoma arises most often near the vermis, the narrow worm-like bridge that connects the cerebellum’s two sides. In adults this tumor tends to occur in the body of the cerebellum, especially toward the edges.
Medulloblastoma is the most common of the embryonal tumors — tumors that arise from
“embryonal” or “immature” cells at the earliest stage of their development.
How is a medulloblastoma diagnosed?
Obtaining a symptom history and performing a neurological examination will be your doctor’s first steps in making a diagnosis. Magnetic resonance imaging (MRI), done both with and without a contrast dye, is then used to identify the presence of a tumor in the brain. The contrast dye is given intravenously (into the vein) to enhance the pictures. By concentrating in abnormal tissue, the dye makes a tumor appear much brighter than other areas.
How is it treated?
Current treatment consists of surgically removing as much tumor as possible, followed by
radiation therapy and/or chemotherapy. Your doctor will suggest a treatment plan based on factors that indicate the risk of tumor recurrence — either “average-risk”or “high-risk.” To determine risk, doctors look at the age of the patient; the amount of tumor remaining following surgery.