Epidemiology

Medulloblastoma is the most common malignant brain tumor of childhood. In the US, there is an average annual incidence rate of 0.41 per 100,000 in children ages ≤19 years.[5]​ The age of diagnosis is highest in the 1-4 and 5-9 age groups, with an annual average incidence rate of 0.59 per 100,000 and 0.63 per 100,000 respectively. The average annual incidence rate then declines in the 10-14 age group (0.33 per 100,000) and 15-19 age group (0.16 per 100,000).[5]​ Overall incidence appears to have remained stable over the years.[6][7]​​

Between 2001 and 2010 in Great Britain (England, Scotland, and Wales), there were 4166 registered central nervous system tumors among children <15 years. Embryonal tumors made up 17% of these, of which 73% were medulloblastoma.[8] There is a slight male predominance; incidence in Great Britain among males has been reported at 0.51 per 100,000 and 0.30 per 100,000 for females.[5]​​ 

There are a few reports of familial medulloblastomas in monozygotic twins.[9][10]​ Medulloblastomas have a marked propensity to seed within the cerebrospinal fluid pathways, with evidence of such metastatic spread occurring in between 11% and 43% of cases at diagnosis.[11][12]​​​​ 

Use of this content is subject to our disclaimer