A posterior fossa tumor is a brain tumor found at the bottom of the skull. These tumors are usually primary brain cancers. If they grow large enough they may block the flow of spinal fluid, cause increased pressure on the brain and spinal cord and damage the cranial nerves. Symptoms caused by these tumors include:
Surgery is used to remove posterior fossa tumors, even if they are not cancerous, because the presence of the tumor can damage other nerves and other structures in the brain. Radiation treatment may also be used.