Medulloblastoma is a type of brain tumor in which benign (noncancerous) or malignant (cancerous) cells form in the tissues of the brain. It usually forms in the cerebellum, which is located at the lower back of the brain. The cerebellum is the part of the brain that controls:
- Movement
- Balance
- Posture.
Medulloblastomas are usually found in children or young adults between 21 and 40 years of age. Although cancer is rare in children, brain tumors are the most common type of childhood cancer other than
leukemia and lymphoma. Approximately 1 out of 5 childhood brain tumors is a medulloblastoma. Medulloblastoma can also be called primitive neuroectodermal tumor (PNET). This type of medulloblastoma can occur in the cerebrum.
No one knows the exact causes of medulloblastoma, and doctors can seldom explain why one person will get it and another person will not.
Symptoms of Medulloblastoma
Symptoms vary, depending on the child's age and where the tumor is located. Common symptoms of medulloblastoma include:
- Loss of balance, difficulty walking, handwriting that becomes worse, or slow speech
- Morning headache or a headache that goes away after vomiting
- Nausea and vomiting
- Unusual sleepiness or change in energy level
- Change in personality or behavior
- Unexplained weight loss or weight gain.
These possible medulloblastoma symptoms, however, are not sure signs of a brain tumor. Other health problems can also cause these symptoms. People who have possible symptoms of medulloblastoma should see a doctor as soon as possible, because only a doctor can diagnose and treat the problem.
When making a diagnosis, the healthcare provider will perform a physical exam, ask about the child's personal and family medical history, and recommend additional tests and procedures.
Exams and tests that are used in diagnosing medulloblastoma may include:
- Computed tomography (CT) scan
- Magnetic resonance imaging (MRI) scan
- Biopsy.
Risk Groups for Medulloblastoma
After medulloblastoma has been treated, tests will need to be done to determine if there is tumor remaining or if cancer cells have spread. For most cancers, the extent or spread of cancer is usually described as stages. For childhood medulloblastoma, risk groups are used instead of cancer stages. Risk groups are described by the amount of remaining tumor or spread of cancer cells within the central nervous system (brain and spinal cord) or to other parts of the body. It is important to know the risk group in order to plan treatment. Risk groups that are used for childhood medulloblastoma are:
Different types of medulloblastoma treatment are available for children. Treatment options vary based on:
- The type of medulloblastoma
- The size and location of the tumor
- The medulloblastoma risk group (see Medulloblastoma Risk Groups)
- The patient's age and general health.
In general, treatment includes:
- Surgery
- Chemotherapy
- Radiation therapy
- Cerebrospinal fluid diversion.
Parents of children with cancer should work with their child's doctor to develop a treatment plan that meets their child's medical needs and the family's personal values. Choosing treatment for medulloblastoma is a decision that ideally involves the patient, the family, and the healthcare team.
Prognosis for Medulloblastoma
A person's prognosis will depend on:
- The age of the child when the tumor is found
- The location of the tumor
- The amount of tumor remaining after surgery
- Whether the cancer has spread to other parts of the central nervous system or to other parts of the body, such as the bones.
Key information about medulloblastoma includes:
- Childhood medulloblastoma is a disease in which benign (noncancerous) or malignant (cancerous) cells form in the tissues of the brain
- The cause of most childhood brain tumors, including medulloblastoma, is unknown
- The signs of childhood medulloblastoma vary, depending on the child's age and where the tumor is located
- Tests that examine the brain and spinal cord are used to find childhood medulloblastoma
- Childhood medulloblastoma is diagnosed and removed in surgery
- Certain factors affect prognosis (chance of recovery) and treatment options.
