Risk Factors

A risk factor is anything that increases a person’s chance of developing a tumor. Some risk factors can be controlled, such as smoking, and some cannot be controlled, such as age and family history. Although risk factors can influence the development of a tumor, most do not directly cause a tumor. Some people with several risk factors never develop a tumor, while others with no known risk factors do.

The cause of a CNS tumor in children is not known. Researchers are studying a variety of possible causes of CNS tumors, including viruses. Different types of CNS tumors occur in different age groups. For example, some types of CNS tumors are more common in children under age three. Head injury does not appear to cause a CNS tumor.

A small number of CNS tumors occur in families. However, only a small percentage of children with a brain tumor have identifiable genetic causes, usually in association with a familial disease called neurofibromatosis. Neurofibromatosis is an inherited disorder that causes neurofibromas (noncancerous tumors) to form on peripheral nerves in the body, brown spots on the skin, and deformities of tissues and bones. Neurofibromatosis is also called Recklinghausen’s disease or von Recklinghausen’s disease. Learn more about neurofibromatosis Type 1 and neurofibromatosis Type 2. Other, less common genetic conditions associated with a higher risk of a CNS tumor include Li-Fraumeni syndrome, tuberous sclerosis, nevoid basal cell syndrome, and Turcot syndrome.