What are the other Names for this Condition? (Also known as/Synonyms)

• Ewing's Family of Tumors (EFT) - Medulloblastoma (Adult)
• Infratentorial PNET (iPNET) - Medulloblastoma (Adult)
• PNET (Primitive Neuroectodermal Tumors) - Medulloblastoma (Adult)

What is Medulloblastoma in Adults? (Definition/Background Information)

Ewing’s Family of Tumors includes the following tumors:

• Ewing’s Sarcoma of Bone
• Extraosseous Ewing’s Tumor
• Primitive Neuroectodermal Tumor (PNET), including Medulloblastoma - Adult type and Medulloblastoma - Childhood type
• Askin’s Tumor: This tumor is also sometimes called, Primitive Neuroectodermal Tumor of Chest Wall, and Ewing’s Sarcoma of Chest Wall
• Primary Cutaneous Ewing’s Sarcoma (PCES)

All the above-mentioned tumors arise from a primitive stem cell.

The brain plays several vital functions in our bodies. It is divided into three parts: Cerebellum, cerebrum, and the brainstem

• Adult Medulloblastoma is a type of brain cancer that typically occurs in the cerebellum of the brain
• The cerebellum is located at the lower, rear region of the brain and is responsible for controlling balance, movement, and posture
• Though, Medulloblastoma usually starts in the cerebellum, it can quickly spread to neighboring regions of the brain
• It is possible for the tumor to pass into the cerebrospinal fluid, which bathes the brain and spinal cord, leading to its spread, to other parts of the central nervous system. Medulloblastoma rarely spreads to other regions of the body

Brain cancer results, when genetic mutations transform normal, healthy brain cells into abnormal cancer cells. Unlike normal cells, these cancer cells have the lost the ability to regulate their growth and do not ‘die-off’ on their own. As a result, they grow and divide uncontrollably, leading to the formation of tumors or masses.

• Brain tumors, like Medulloblastoma, occupy space inside the skull. But, since the skull is a hard bone, it cannot expand
• Therefore, the tumor begins pressing on the brain, impairing important brain functions. Pressure on the brain leads to symptoms, such as headaches, nausea, vomiting, loss of balance, and sleepiness
• Medulloblastoma is a rare condition; it is an uncommon, cancerous, central nervous system tumor in adults

Medulloblastoma is a type of Primitive Neuroectodermal Tumor (PNET). PNETs are classified as:

• Primitive Neuroectodermal Tumor of the Central Nervous System (PNET of the CNS)
• Peripheral Primitive Neuroectodermal Tumors - tumors that occur outside the central nervous system

Primitive Neuroectodermal Tumor of the Central Nervous System is divided into 2 types, based upon their location in the brain, namely:

• Infratentorial PNET (iPNET) : iPNETs are Medulloblastomas
• Supratentorial PNET (sPNET)

Who gets Medulloblastoma in Adults? (Age and Sex Distribution)

• Only 1% of the brain tumors in adults are Medulloblastomas. This condition is very rare in adults, and the incidence rate is about 0.5 per million, per year
• Studies in the US shows that 33% of all Medulloblastomas are detected in individuals, in the age group 20-44 years. This condition is extremely infrequent in adults over 45 years of age
• Medulloblastoma is most common in children between ages 3-8 years; it can be seen in children and adults of any age. However, Medulloblastoma is much less common in adults, than in children
• Caucasians are affected slightly more, than African Americans

What are the Risk Factors for Medulloblastoma in Adults? (Predisposing Factors)

It is important to recognize that this (Medulloblastoma) and other brain cancer types can occur, with no known cause. However, Adult Medulloblastoma is associated with the following genetic conditions, which include:

• Li-Fraumeni syndrome
• Nevoid basal cell carcinoma syndrome (Gorlin syndrome)

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases ones chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.

Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.

What are the Causes of Medulloblastoma in Adults? (Etiology)

• The cause of Adult Medulloblastoma is currently unknown
• Like all other types of cancer, Medulloblastoma is caused by genetic changes that turn healthy cells into cancer cells. These cancer cells have lost the ability to control their growth, leading to the formation of tumors
• Adult Medulloblastoma tumors can invade other parts of the brain and spinal cord. In more rare cases, the tumor spreads to others regions of the body

What are the Signs and Symptoms of Medulloblastoma in Adults?

The signs and symptoms of Adult Medulloblastoma include:

• Morning nausea and vomiting
• Morning headaches that gradually improve as the day progresses
• Loss of balance, difficulty walking, slurred speech, problems with handwriting, blurred vision
• Sleepiness, irritability,
• Personality or behavioral changes; the individual may remain socially aloof
• Changes in appetite

How is Medulloblastoma in Adults Diagnosed?

Diagnostic tools for Adult Medulloblastoma include:

• Physical exam with complete medical history evaluation
• Neurological exam: Test of all brain and spinal functions
• Computed tomography (CT) scan of brain: A CT scan involves using an x-ray machine linked to a computer, to provide a series of detailed images of the brain. This helps to show the size and location of the tumor
• Magnetic Resonance Imaging (MRI) scan of brain: MRI scan is a common diagnostic test that produces images of the brain and its structure. Sometimes, a dye may be injected into a blood vessel in the arm, to help differentiate tissues in the brain
• Biopsy of tumor: In order to confirm a diagnosis for Adult Medulloblastoma, a biopsy may be performed. This involves removing a sample of tumor tissue using a needle, followed by microscopic examination of the sample by a pathologist, to look for cancer cells

There are other tests that can be performed to determine if the brain tumor has spread to the other areas of the body, including to the spine or bones:

• Spine MRI scans: For a spine MRI, a sedative may be given to the individual, as the procedure requires that individuals ‘lie very still’, during the scan. A contrast dye may also be used, to help detect the locations of the abnormal cells
• Spinal tap: A spinal tap involves the removal of a small sample of cerebrospinal fluid (CSF) to test for cancer cells in the spine. It is done using a long, thin needle, which is placed in the region, between the spinal bones and spinal cord. This is the location where CSF flows. A sedative will most likely be used for individuals undergoing a spinal tap, as it can be quite uncomfortable
• Bone marrow aspiration and biopsy: By inserting a hollow needle into the hipbone or breastbone - bone marrow, blood, and a small piece of bone, is removed. Microscopic examination by a pathologist, will then determine the presence of cancer in the bone
• Bone scan: This procedure helps to detect any cancer cells in the bone using a small amount of radioactive material, which is injected into a vein. The radioactive material travels throughout the bloodstream, collects in the bones, and is detected by a scanner

Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.

What are the possible Complications of Medulloblastoma in Adults?

There are some complications that could possibly arise as a result of the treatment for Adult Medulloblastoma. These could include:

• Following surgery, individuals with Adult Medulloblastoma may experience difficulty with coordination and balance, which normally lasts for several weeks
• Posterior fossa mutism is another condition that may arise within 24-hours after surgery. With this condition, an individual may develop an inability to speak and may have difficulty with balance and swallowing. This condition can range from mild to severe
• About 15% of the individuals develop another complication, called hydrocephalus (fluid build-up in the skull). It requires a special procedure to drain spinal fluid

How is Medulloblastoma in Adults Treated?

The standard treatment options for Adult Medulloblastoma are surgery, radiation therapy, chemotherapy, cerebrospinal fluid diversion, and endoscopic third ventriculostomy.

• Surgery:  Surgery is used to remove all or most of the brain tumor, as well as to relieve hydrocephalus (the build-up of fluid in the skull). It has been shown that the more of the tumor removed, the better the outcome for the patient
• Radiation therapy: Radiation therapy uses high-energy waves to ‘kill-off’ any remaining cancer cells and to shrink tumors, following surgery. There are 2 types of radiation therapy:
  • External radiation therapy - which involves placing a machine placed outside of the body that aims radiation at the brain cancer
  • Internal radiation therapy - during which radiation is placed within the brain. It uses radioactive substances, which are sealed in seeds near the cancer, to emit radiation
• Chemotherapy: Chemotherapy uses drugs to kill cancer cells, or to prevent the advancement of their growth. These drugs, which may be taken orally in pill form, or may be injected into a vein, travel throughout the bloodstream, to kill the cancer cells
• Cerebrospinal fluid diversion: With Adult Medulloblastoma, the tumor in the brain can block the flow of cerebrospinal fluid, which surrounds the brain and spinal cord. During cerebrospinal fluid diversion, a shunt, or long tube, is placed in a ventricle of the brain and threaded underneath the skin, to another area of the body. Typically, it is threaded to the abdomen. This shunt carries extra fluid away from the brain
• Endoscopic third ventriculostomy (ETV): ETV can also be used to relieve the brain of hydrocephalus, or fluid build-up. In this procedure, a small hole is created that allows fluid to move around the blockage created by the tumor, and into the spinal column

How can Medulloblastoma in Adults be Prevented?

• As with other types of brain cancer, the exact cause of Adult Medulloblastoma is not known, and the condition cannot be prevented
• Cancer screenings are important in that they can detect cancer in its earliest stages, which would help optimize treatment efforts. However, currently, there are no standardized screening tests available for Adult Medulloblastoma

What is the Prognosis of Medulloblastoma in Adults? (Outcomes/Resolutions)

• The prognosis for individuals with Adult Medulloblastoma is dependent on several factors. These include:
  • Individual’s age and health status, at the time of diagnosis
  • Tumor type and grade
  • Size and location of the tumor
  • If the tumor can be removed through surgery and the amount of tumor mass that can be safely removed
  • Whether the tumor has recurred, or has spread to other areas of the body
• However, the prognosis of Medulloblastoma in Adults is much worse than, when children are affected by the condition. Also, late relapses are more common in adults, than children. Hence, one has to be more watchful and closer follow-ups are necessary
• There may be damages to healthy tissues, as a result of chemotherapy and radiation therapy, leading to long-term effects. These include:
  • Hearing loss
  • Hormonal problems
  • Secondary tumors
• It is suggested that individuals treated for Adult Medulloblastoma be evaluated every year, to monitor disease complications, be screened for recurrence of brain tumor, and to manage the effects of treatment

Additional and Relevant Useful Information for Medulloblastoma in Adults:

• Every year, about 500 cases of Childhood Medulloblastoma are diagnosed in the U.S. The number of cases is far less, for Adult Medulloblastoma
• Current evidence shows that Peripheral Primitive Neuroectodermal Tumors (tumors that occur outside the central nervous system) are considered to be similar to Ewing’s Sarcoma
• There are different types of Medulloblastoma based on histological factors, as determined by a pathologist. These include:
  • Classic medulloblastoma
  • Desmoplastic nodular medulloblastoma
  • Large-cell or anaplastic medulloblastoma
  • Medulloblastoma with neuroblastic or neuronal differentiation
  • Medulloblastoma with glial differentiation
  • Medullomyoblastoma
  • Melanotic medulloblastoma