Medulloblastoma

July 30, 2025

This page was reviewed under our medical and editorial policy by Leo David Wang, M.D., Ph.D., associate professor, Department of Pediatrics, City of Hope^® Cancer Center Duarte. 

Medulloblastoma is a type of cancer that affects the brain or spinal cord. Around 7 in 10 patients diagnosed with medulloblastoma are children, with most diagnoses before the age of 10. Around 450 new cases of medulloblastoma are diagnosed every year in the United States.

What Is Medulloblastoma?

Medulloblastoma is a cancer that develops in the body’s primary central nervous system, which includes the brain and the spinal cord. Although 70% of medulloblastoma diagnoses are in children or adolescents, the disease may affect adults, too.

The most common location for a medulloblastoma tumor is in the cerebellum, which is a part of the brain at the back of the head. The cerebellum is between the cerebrum and the brainstem, which is the point where the brain connects to the spinal cord.

Medulloblastoma Symptoms

It’s important to know some of the common symptoms and signs of medulloblastoma in children and infants. They include:

• Headaches that mostly occur in the mornings
• Feeling nauseated or vomiting
• Changes to vision, such as double vision or blurred vision
• Behavior changes, such as being more confused, irritable or sleepy than usual
• Problems sitting or standing without help

In some cases, a child’s doctor may notice signs that could indicate medulloblastoma during a routine checkup. These include swelling around the fontanelle (the soft spot at the center of an infant’s skull) or an unexpected increase in head size.

What Causes Medulloblastoma?

Cancer develops when normal cells begin to grow out of control and form tumors. As with most childhood cancers, doctors and scientists don’t yet know exactly what causes medulloblastoma. However, a few rare inherited conditions slightly increase the risk that a child will develop medulloblastoma, including familial adenomatous polyposis (FAP, or Turcot syndrome) and nevoid basal cell carcinoma syndrome (NBCCS, or Gorlin syndrome).

Diagnosis and Testing

If doctors suspect that a child may have medulloblastoma, they may recommend several tests to diagnose the condition, including:

• Imaging tests, such as magnetic resonance imaging or computed tomography, that may help determine the location and size of a tumor
• A lumbar puncture, which may be used to take a small sample of cerebrospinal fluid from the spinal cord and then examined under a microscope for signs of cancer

Stages

Staging cancer is the process of using tests to determine how big a tumor is and how far it may have spread. Generally, a higher stage number indicates that a cancer has spread or grown more. When doctors stage medulloblastoma, they give it a number from 0 to 4. The stages of medulloblastoma are:

• M0, which indicates the tumor has not spread from its original location
• M1, which indicates that cancer was found in a patient's cerebrospinal fluid
• M2, which indicates that the tumor has spread from its original site to the brain
• M3, which indicates that cancer has spread from its original site to the spinal cord
• M4, which indicates that cancer has spread outside the central nervous system

Types

There are several different types of medulloblastoma, and they can be classified using histology (what the cancer cells look like under a microscope) or genetics (specific alterations in or to the DNA of the tumor cells). The main histologic subtypes are:

• Classic medulloblastoma, which accounts for around 80% of all childhood medulloblastomas
• Desmoplastic nodular (DN) medulloblastoma, which is the most common type in young infants
• Large-cell anaplastic (LCA) medulloblastoma, which is rarer but more aggressive
• Medulloblastoma with extensive nodularity (MBEN), which mainly affects younger children or infants

Increasingly, genetic classification is becoming the main way of classifying medulloblastomas. The genetic subtypes are:

• Wnt-activated
• SHH-activated, either TP53-mutant or TP53-wildtype, in which there are 4 methylome-based subgroups
• Non-Wnt, non-SHH (group 3 and 4), in which there are 8 methylome-based subgroups

Medulloblastoma Treatment

An effective treatment plan for medulloblastoma often includes more than one treatment type and is based on factors including the cancer's stage and the patient’s age.

Surgery for Medulloblastoma

The main initial treatment option for most medulloblastomas is surgery to remove as much of the tumor as possible. Surgical treatment also allows doctors to collect a sample of the tumor in order to determine its type.

Chemotherapy for Medulloblastoma

Most medulloblastoma patients also receive ​​chemotherapy after they have undergone surgery. Chemotherapy is the term for a wide range of medications that are delivered into a vein (intravenous chemotherapy) or by mouth (oral chemotherapy) and are designed to kill cancer cells in the body. In rare cases, patients under 3 may be given high-dose chemotherapy, followed by a stem cell transplant, if their cancer is more advanced or more aggressive.

Radiation Therapy for Medulloblastoma

​​Radiation therapy is often recommended in combination with chemotherapy for pediatric medulloblastoma patients aged 3 and over. Children under age 3 do not usually receive radiation therapy, because it may cause damage to the brain as it is growing and developing.

Radiation therapy involves aiming high-powered beams of radiation at the site of the tumor from outside the body. Proton beam therapy is a specific kind of radiation therapy that may be used to treat medulloblastoma. Some children may require anesthetic in order to remain still during radiation treatments.

Who Treats Medulloblastoma?

Children and adolescents diagnosed with medulloblastoma are cared for by a multidisciplinary team of children’s cancer experts, which may include:

• Pediatric oncologists, who are experts in childhood cancers
• Surgical oncologists and neurosurgeons, who work together to remove tumors from the brain or spinal cord
• Neurologists, who are specialists in treating central nervous system disorders
• Medical oncologists with expertise in using medicines like chemotherapy to treat cancer
• Radiation oncologists, who specialize in using radiation therapy techniques
• Supportive care staff offering access to both physical and emotional support during and after treatment
• Trained oncology nurses, who care for patients during their hospital treatments
• Pathologists, who are experts in examining tissue samples to determine the type of cancer a patient has

Complications

Some potential long-term complications may affect patients who receive treatment for medulloblastoma. Studies have found that, in later life, some medulloblastoma survivors may experience:

• Hearing loss or changes to how some of the senses work
• Problems with the endocrine system, which produces a range of hormones that help regulate how the body works
• Decreases in cognitive ability over time
• A secondary cancer diagnosis

Posterior Fossa Syndrome

Some children who undergo surgery to remove a medulloblastoma tumor experience a condition called posterior fossa syndrome, which affects a section of the brain that helps control motor skills, balance and some other bodily functions. The symptoms of posterior fossa syndrome usually appear within a week of surgery and may last for several months. They include:

• Trouble with speech or being unable to speak
• Problems managing emotions or being irritable
• Balance or movement issues that can cause trouble walking

Patients with posterior fossa syndrome usually undergo a variety of therapies to help them improve or recover their speech and motor skills.

Medulloblastoma Prognosis

The prognosis for children with medulloblastoma varies based on a range of factors, including their age, what type of medulloblastoma they have, how far it has spread and their response to treatment.

The overall five-year survival rate for medulloblastoma is about 80%.

The five-year survival rate for children under 3 ranges from 30% to 70%.

A patient’s care team is able to provide a personalized prognosis based on his or her specific diagnosis, subtype, stage and overall health.