Medulloblastoma

Medulloblastoma is the most common cancerous brain tumor in children. Treatment usually includes a combination of surgery, radiation and chemotherapy.

Update Date: 21.02.2025

Overview
Symptoms
Causes
Risk factors
Diagnosis
Treatment
Preparing for an appointment
Overview
Symptoms
Causes
Risk factors
Diagnosis
Treatment
Preparing for an appointment

Overview

Medulloblastoma (muh-dul-o-blas-TOE-muh) is a cancerous brain tumor that starts in the lower back part of the brain. This part of the brain is called the cerebellum. It is involved in muscle coordination, balance and movement.

Medulloblastoma begins as a growth of cells, which is called a tumor. The cells grow quickly and can spread to other parts of the brain. Medulloblastoma cells tend to spread through the fluid that surrounds and protects your brain and spinal cord. This is called cerebrospinal fluid. Medulloblastomas don't usually spread to other parts of the body.

Medulloblastoma can happen at any age, but most often occurs in young children. Though medulloblastoma is rare, it's the most common cancerous brain tumor in children. Medulloblastoma happens more often in families that have a history of conditions that increase the risk of cancer. These syndromes include Gorlin syndrome or Turcot syndrome.

Medulloblastoma

Medulloblastoma is a type of brain cancer that starts in the part of the brain called the cerebellum. Medulloblastoma is the most common type of cancerous brain tumor in children.

Symptoms

Medulloblastoma symptoms happen when the cancer grows or causes pressure to build up in the brain. Signs and symptoms of medulloblastoma may include:

  • Dizziness.
  • Double vision.
  • Headaches.
  • Nausea.
  • Poor coordination.
  • Tiredness.
  • Unsteady walk.
  • Vomiting.

When to see a doctor

Make an appointment with a doctor or other healthcare professional if you have any symptoms that worry you.

Medulloblastoma

Medulloblastoma is a type of brain cancer that starts in the part of the brain called the cerebellum. Medulloblastoma is the most common type of cancerous brain tumor in children.

Causes

It's not clear what causes medulloblastoma. This cancer starts as a growth of cells in the brain.

Medulloblastoma happens when cells in the brain develop changes in their DNA. A cell's DNA holds the instructions that tell the cell what to do. In healthy cells, the DNA gives instructions to grow and multiply at a set rate. The instructions tell the cells to die at a set time. In cancer cells, the DNA changes give different instructions. The changes tell the cancer cells to grow and multiply quickly. Cancer cells can keep living when healthy cells would die. This causes too many cells.

The cancer cells form a mass called a tumor that can grow to push on nearby structures. The cancer cells can invade and destroy healthy body tissue. They also can spread to other areas.

Risk factors

Factors that may increase the risk of medulloblastoma include:

  • Young age. Medulloblastoma can happen at any age. This cancer happens most often in children.
  • Inherited syndromes. Medulloblastoma happens more often in families that have a history of conditions that increase the risk of cancer. These conditions include Fanconi anemia, Gorlin syndrome, Li-Fraumeni syndrome, Rubinstein-Taybi syndrome and Turcot syndrome.

Diagnosis

The process of diagnosis usually starts with a medical history review and a discussion of signs and symptoms. Tests and procedures used to diagnose medulloblastoma include:

  • Neurological exam. During this exam, vision, hearing, balance, coordination and reflexes are tested. This can help show which part of the brain might be affected by the tumor.
  • Imaging tests. Imaging tests capture pictures of the brain. The pictures can show the size and location of the tumor. These tests may show pressure or blockages of the cerebrospinal fluid. CTs and MRIs are used for the imaging, but other tests might be needed in certain situations.
  • Tissue sample testing. A biopsy is a procedure to remove a sample of the tumor for testing. Biopsies for medulloblastoma are uncommon but might be used in certain situations. In a biopsy, part of the skull is removed. A needle is used to take a sample of the tumor. The sample is tested in a lab to see if it's a medulloblastoma.
  • Removal of cerebrospinal fluid for testing. A spinal tap, also called a lumbar puncture, involves inserting a needle between two bones in the lower spine. The needle draws out cerebrospinal fluid from around the spinal cord. The fluid is tested in a lab to look for tumor cells. This test is only done after managing the pressure in the brain or removing the tumor.

Treatment

Treatment for medulloblastoma usually includes surgery followed by radiation or chemotherapy, or both. Your healthcare team considers many factors when creating a treatment plan. These factors might include the tumor's location, how fast it's growing, whether it has spread to other parts of the brain and the results of tests on the tumor cells. Your care team also considers your age and your overall health.

Treatment options include:

  • Surgery to relieve fluid buildup in the brain. A medulloblastoma may grow to block the flow of cerebrospinal fluid. This can cause a buildup of fluid that puts pressure on the brain. To reduce the pressure, a surgeon can create a pathway for the fluid to flow out of the brain. Sometimes this procedure can be combined with surgery to remove the tumor.
  • Surgery to remove the medulloblastoma. The goal of surgery is to remove all of the medulloblastoma. But sometimes it's not possible to fully remove the tumor because it forms near important structures deep within the brain. Most people with medulloblastoma need more treatments after surgery to kill any cancer cells that are left.
  • Radiation therapy. Radiation therapy uses powerful energy beams to kill cancer cells. The energy can come from X-rays, protons and other sources. During radiation therapy, a machine directs beams of energy to specific points on the body. Radiation therapy is often used after surgery.
  • Chemotherapy. Chemotherapy uses medicines to kill cancer cells. Typically, children and adults with medulloblastoma receive these medicines as an injection into veins. Chemotherapy may be used after surgery or radiation therapy. Sometimes it's done at the same time as radiation therapy.
  • Clinical trials. Clinical trials enroll eligible participants to study new treatments or to study new ways of using existing treatments, such as different combinations or timing of radiation therapy and chemotherapy. These studies provide a chance to try the latest treatment options, though the risk of side effects may not be known. Talk with your healthcare professional for advice.

Preparing for an appointment

Make an appointment with a doctor or other healthcare professional if you have any symptoms that worry you.

Because appointments can be brief, it's a good idea to be prepared. Here's some information to help you get ready.

What you can do

  • Be aware of anything you need to do ahead of time. At the time you make the appointment, be sure to ask if there's anything you need to do in advance, such as restrict your diet.
  • Write down symptoms you have, including any that may not seem related to the reason for which you scheduled the appointment.
  • Write down important personal information, including major stresses or recent life changes.
  • Make a list of all medicines, vitamins or supplements you're taking and the doses.
  • Take a family member or friend along. Sometimes it can be very hard to remember all the information provided during an appointment. Someone who goes with you may remember something that you missed or forgot.
  • Write down questions to ask your healthcare team.

Your time with your healthcare team is limited, so preparing a list of questions can help you make the most of your time together. List your questions from most important to least important in case time runs out. For medulloblastoma, some basic questions to ask include:

  • Do I have a medulloblastoma?
  • Will I need more tests?
  • Can my medulloblastoma be removed?
  • Why do I need additional treatments if surgery removes the entire medulloblastoma?
  • What are the treatment options?
  • What is the stage of my medulloblastoma?
  • Has my medulloblastoma spread to other parts of my body?
  • How much does each treatment increase my chances of a cure or prolong my life?
  • What are the potential side effects of each treatment?
  • How will each treatment affect my daily life?
  • Is there one treatment option you believe is the best?
  • What would you recommend to a friend or family member in my situation?
  • Should I see a specialist?
  • Are there any brochures or other printed material that I can take with me? What websites do you recommend?
  • What will determine whether I should plan for a follow-up visit?
  • Will I need to continue coming back?

Don't hesitate to ask other questions.

What to expect from your doctor

Be prepared to answer questions, such as:

  • When did your symptoms begin?
  • Have your symptoms been continuous or occasional?
  • How severe are your symptoms?
  • What, if anything, seems to improve your symptoms?
  • What, if anything, appears to worsen your symptoms?

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