What Is Medulloblastoma?

Medulloblastoma is the most common cancerous (malignant) type of brain tumor. It develops in the cerebellum, a part of the brain near the bottom of the skull.

Doctors usually treat kids who have this type of tumor with a combination of surgery, chemotherapy, and radiation therapy. Treatment has improved in recent years, and more kids are making a full recovery.

What Are the Signs & Symptoms of Medulloblastoma?

When cells grow abnormally or out of control, a tumor (a mass of cells) can form. A tumor in the brain can put pressure on areas of the brain, leading to different symptoms, such as:

• nighttime or early-morning headaches
• nausea
• vomiting
• trouble walking
• dizziness
• double vision
• clumsiness

What Causes Medulloblastoma?

Doctors don't know what causes medulloblastoma (meh-dull-oh-blas-TOE-muh). But some genetic conditions can make kids more likely to develop it. About 20% of all brain tumors in children are medulloblastomas.

How Is Medulloblastoma Diagnosed?

When doctors suspect a brain tumor, they’ll do an exam and order an imaging test of the brain, like an MRI (magnetic resonance imaging). This test lets them see inside the brain to find any areas that look abnormal.

If tests show a brain tumor, doctors may do surgery to safely remove as much of it as they can. They’ll test a sample of the tumor for DNA changes known as molecular markers. These changes help doctors learn more about the medulloblastoma and make a treatment plan.

Medulloblastoma cells can spread to other areas of the brain and spine, so doctors will do more tests, including:

• an MRI of the spine
• a lumbar puncture (spinal tap) to get a small sample of cerebrospinal fluid

How Is Medulloblastoma Treated?

Doctors usually treat medulloblastoma with a combination of surgery, chemotherapy, and radiation therapy. When making a treatment plan, they'll consider:

• the child's age
• the size of the tumor
• test results on the tumor cells
• molecular markers

After they remove as much of the tumor as possible with surgery, doctors can use chemotherapy (chemo) medicines and radiation therapy to prevent the tumor from coming back or spreading.

Radiation therapy uses X-rays (photon therapy) or proton beam therapy to kill cancer cells and shrink tumors. It's often used to destroy cancer cells still in the brain after surgery and cancer cells in the spinal cord. In children younger than 3 years old, radiation therapy is avoided because it can affect brain growth and development. 

Chemotherapy uses medicines to kill cancer cells. It can be given in many different ways. Medicines often used include cisplatin, vincristine, and cyclophosphamide.

New information about genetic changes in medulloblastoma tumors has led to many new treatments that specifically target these changes. They are being used with increasing success in children with brain tumors.

Doctors are always looking for better ways to treat medulloblastoma. Some patients might be candidates for a clinical trial. Talk to the doctor about whether this might be a good option for your child.

Who Is on the Care Team?

A team of specialists works together to care for a child with medulloblastoma. They may include:

• a pediatric neuro-oncologist (a doctor who treats cancers of the brain or spine)
• a pediatric neurologist (a doctor who treats nervous system problems)
• a pediatric neurosurgeon (a surgeon who operates on the brain or spine)
• a pediatric radiation oncologist (a specialist who gives radiation therapy)
• pediatric rehabilitation medicine specialists, including speech therapists, physical therapists, and occupational therapists
• pediatric psychologists and social workers

What Else Should I Know?

If your child has medulloblastoma, it can feel overwhelming. It’s normal to feel sad, scared, and even angry. It helps to find support from members of the care team, friends and family, and other parents who’ve gone through it.

When talking about it with your child, it’s best to be honest, but give information that fits your child’s age and emotional maturity. Make sure kids know that the tumor isn’t the result of anything they did. If you need help answering questions, or don’t know what to say, a member of the care team can help.

The future for kids with brain tumors is better than ever. You can find more information and support online at:

• American Cancer Society
  
• National Cancer Institute
• Pediatric Brain Tumor Foundation