A Medulloblastoma is a malignant brain tumor that originates either in the posterior fossa or the cerebellum part of the brain.
Medulloblastoma have a distinct molecular profile that sets them apart from other tumors. They are invasive and grow very quickly, spreading through the cerebrospinal fluid and often metastasizing. Medulloblastoma occur most frequently in those under the age of 20, and especially in those under age five.
There is a higher incidence of these tumors in boys than there is in girls. The exact cause is not known, but it is believed that they may be caused by stem cells that have not divided correctly.
Signs & Symptoms
People who suffer from a Medulloblastoma may experience pressure in their skull due to the blockage of the fourth ventricle, which is where the Medulloblastoma tumors are normally found. The tumor may be there for one to five months before it is discovered and properly diagnosed. In children their symptoms progress from listlessness, vomiting and headaches to stumbling, falling, diplopia, dizziness, and motor weakness.
Diagnosis
An MRI is used to diagnoses most Medulloblastoma. Their location in the fourth ventricle and their appearance are strong indicators to physicians as to what they are dealing with. Medulloblastoma are generally solid masses that are pink or gray in color. They have a lot of mitoses and clusters of rosettes. Ruling out atypical teratoid rhabdoid tumors (ATRT) also needs to be done.
Treatment
Typical treatment for Medulloblastoma includes surgery to remove the tumor. Radiation and chemotherapy treatments in addition to surgery greatly decrease the chances of the disease recurring. If skull pressure continues this can be treated with the use of corticosteroids or a shunt.
Prognosis
With proper and timely diagnosis and treatment of Medulloblastoma there is a survival rate of approximately five years. This has shown to be true in approximately 80% of the cases. Recurrence of the disease is usually fatal so it is important to do everything possible to avoid this from happening. Children under the age of three whose Medulloblastoma has already spread have a less favorable prognosis.
