Disease Overview

Medulloblastomas can affect individuals of any age, but occur most often in children under the age of 15 with a peak incidence between 3 and 9 years of age. Medulloblastomas are the most common malignant brain tumor in children. Approximately 80 percent of affected individuals are under the age of 15. Medulloblastomas are extremely rare in adults accounting for 1-2 percent of all cases of brain tumors in adults. In adults, most medulloblastomas occur in individuals between 20-44 years of age. Medulloblastomas are extremely rare in individuals over the age of 45.

In children, males are affected more often than females. However, in adults the ratio is the same. The exact incidence of medulloblastomas is not known and many different estimates are given the
medical literature. Generally, medulloblastomas account for 2 percent of all primary brain tumors and 18 percent of all pediatric brain tumors. Approximately 1,000 new cases are diagnosed in children and adults each year in the United States.