Medulloblastoma (muh-dul-o-blas-TOE-muh) is a cancerous (malignant) brain tumor that starts in the lower back part of the brain, called the cerebellum. The cerebellum is involved in muscle coordination, balance and movement.

Medulloblastoma tends to spread through cerebrospinal fluid (CSF) — the fluid that surrounds and protects your brain and spinal cord — to other areas around the brain and spinal cord. This tumor rarely spreads to other areas of the body.

Medulloblastoma is a type of embryonal tumor — a tumor that starts in the fetal (embryonic) cells in the brain. Based on different types of gene mutations, there are at least four subtypes of medulloblastoma. Though medulloblastoma is not inherited, syndromes such as Gorlin's syndrome or Turcot's syndrome might increase the risk of medulloblastoma.

Signs and symptoms of medulloblastoma may include headaches, nausea, vomiting, tiredness, dizziness, double vision, poor coordination, unsteady walk and other concerns. These symptoms may be related to the tumor itself or be due to the buildup of pressure within the brain.

Medulloblastoma can occur at any age, but most often occurs in young children. Though medulloblastoma is rare, it's the most common cancerous brain tumor in children. Children need to be seen at a center that has a team of pediatric specialists with expertise and experience in pediatric brain tumors, with access to the latest technology and treatments for children.