What is medulloblastoma?
Medulloblastoma, a cancerous tumor that begins within the brain, usually afflicts only children and young adults. Diagnosis of cancer may be confirmed by either of two tests: a computed tomographic (CT) X-ray scan, or a magnetic resonance imaging (MRI) scan. A biopsy—surgical removal of a small amount of tissue — also may be necessary. Treatment effectiveness depends upon the size and location of the tumor and the age of the child.