Medulloblastoma is a type of brain tumor that starts in the cerebellum, which controls balance and other complex motor and cognitive functions. While medulloblastoma often grows quickly and may spread to other parts of the body, it usually responds well to treatment.
In adults, medulloblastoma represents only 1% of all malignant brain tumors. It typically affects younger adults (between 20 and 40 years of age).
Medulloblastomas start in the cerebellum, in the region of the brain at the base of the skull called the posterior fossa. This is the part of the brain that controls balance and other complex motor and cognitive functions. While medulloblastomas often grow quickly and can spread to other parts of the nervous system and the body, especially the bones or bone marrow, they usually respond well to treatment.
Medulloblastoma risk factors
Anything that increases the chance of developing medulloblastoma is a risk factor. Although the cause of medulloblastoma is not known, certain things may increase the risk.
- Age: Most medulloblastoma cases are diagnosed before age 16, and usually between the ages of 3 and 8. In adults, it is rarely seen after the age of 40.
- Gender: it is more common in men than in women.
- Genetic conditions: People with cancer predisposition syndromes like Li-Fraumeni syndrome, Turcot syndrome and Nevoid basal cell carcinoma syndrome (Gorlin syndrome) are more likely to develop medulloblastoma.
The symptoms of medulloblastoma vary from patient to patient Symptoms of medulloblastoma include:
- Headaches, which may be worse in the morning and get better during the day
- Nausea or vomiting in the morning
- Problems with motor skills, such as clumsiness or poor handwriting
- Tilting the head to one side
- Walking difficulty and balance problems
Sometimes medulloblastoma can spread to other parts of the brain and the spinal cord. If this happens, the symptoms may include:
- Back pain
- Difficulty walking
- Inability to control bladder and bowel functions
These symptoms can be caused by something other than medulloblastoma. However, it is important to discuss any symptoms with doctor, since they may signal other health problems.
One or more of the following diagnostic tests may be used to find out if you have medulloblastoma and if it has spread. These tests also may be used to find out if treatment is working.
Imaging tests, including:
- CT (computed tomography) scans
- MRI (magnetic resonance imaging) of the brain and spine
- PET (positive emission tomography) scan
Surgery: If an MRI or CT of the brain shows a tumor in the lower part of the back of the brain, medulloblastoma may be a possibility. In an operation called a craniotomy, all or part of the brain tumor is removed. This is needed to confirm the diagnosis and is the first step of treatment. If tumor removal is not possible, a biopsy may be needed. In a biopsy, a small sample is removed from the tumor and looked at with a microscope to confirm the diagnosis.
In addition to tumor removal, additional tests are required to evaluate how much the disease has spread from its original site and decide the best course of treatment. These tests include:
- A brain MRI obtained after tumor removal
- A whole spine MRI
- A spinal tap, or lumbar puncture). During this procedure, a small amount of cerebrospinal fluid (clear liquid in and around the brain and spine) is removed with a needle from the spinal canal. It is then examined with a microscope to determine if tumor cells have spread into the cerebrospinal fluid.
- A CT or a PET scan of the body may be needed in some cases to determine if the tumor has spread outside of the nervous system
At Department of subtentorial neurooncology, medulloblastoma treatment is carefully designed by a team of highly specialized experts. They take a team approach to deliver the most advanced therapies with the fewest possible short- and long-term side effects, keeping a constant eye on the patient’s quality of life.
Each patient is also cared for by a specially trained staff of nurses, therapists and other care professionals.
Medulloblastoma treatment almost always includes surgery to remove as much of the tumor as possible as safely as possible to minimize damaging the surrounding brain tissue. Studies have shown that if doctors remove more of the tumor, the chances for successful treatment and improved survival are better.
In addition, surgery may be required to treat a condition called hydrocephalus. This occurs when the tumor blocks the cerebral spinal fluid (CSF) surrounding the brain and spine. In this situation, doctors may perform a procedure to divert the CSF.
Like all surgeries, brain tumor surgery is most successful when performed by a specialist with a great deal of experience in the particular procedure. This is especially true with brain tumors, because it is crucial to remove as much of the tumor as possible while leaving intact as much brain function as possible.
Chemotherapy for medulloblastoma
After surgery, most patients may receive chemotherapy in addition to radiotherapy to destroy any remaining cancer cells after surgery. This is an important decision, and it is critical to balance factors such as age, the amount of tumor left after surgery, and whether the cancer has spread to other parts of the nervous system or the body.
Radiation therapy for medulloblastoma
Radiation therapy (also called radiotherapy) uses high-energy beams to destroy cancer cells.
All adults with medulloblastoma receive radiation therapy to the brain and the spine (“craniospinal radiation”) after surgery to stop or slow the growth of any residual tumor that cannot be removed surgically and any tumor cells that may have spread into the cerebrospinal fluid.
Targeted therapies for medulloblastoma
Targeted therapies are specially designed to treat each cancer’s specific genetic/molecular profile to help the body fight the disease.
Our experts are collaborating with experts from around the world to better understand the biology and molecular subtypes of medulloblastoma, including relapsed tumors, to design personalized therapies.