Epidemiology of Supratentorial Ependymomas in Children

Incidence and Prevalence

Ependymomas in general

• Third most common primary brain tumor in children: Ependymomas are the third most common primary brain tumor in children after astrocytomas and neuroectodermal tumors.
• 3–9% of all brain tumors: An estimated 10–15 new cases occur annually in the United Kingdom (7).
• Two-thirds are infratentorial.

Supratentorial ependymomas

• High incidence in parenchyma: While 60% are in the lateral and third ventricles, 40% will be  intraparenchymal within the cerebral hemisphere (8).
• Relatively rare: Most series report small numbers, such as 17 cases over 12 years,  18 cases over 14 years, and 31 cases over 10 years (7, 9, 10).
• Limited published studies: While there are many publications that report on ependymomas, they typically do not distinguish the tumors by location, age-group, or histological type.

Age Distribution

• 6–10 years: The mean age of diagnosis of supratentorial ependymomas is older (6–10 years) than that for infratentorial ependymomas (0–4 years), but the range can be from 1–18 years (11).

Sex Predilection

• Male>female: 2:1.

Geographic Distribution

• No specific geographic distribution

Risk Factors

• None identified: The etiology is unknown.

Relationships to Other Disease States and Syndromes

• None: Although there is some association of neurofibromatosis type 2 (NF2) with intraspinal ependymoma, there is no apparent association with supratentorial ependymomas.