Brain Tumors down arrow

Home > Disclaimer > General Pediatric Brain Tumor

 

General Pediatric Brain Tumor

 

Introduction

 

Central nervous system tumors account for nearly 20 percent of all neoplasms in children under 15 years of age. 

They are the second most common form of pediatric cancer, exceeded only by leukemia. 

Brain tumors remain the leading cause of cancer deaths in pediatric oncology patients.

They differ from adult tumors in some important respects:

  • A greater proportion of pediatric tumors are:
    • Infratentorial
    • Low grade gliomas (hemispheric high grade gliomas are rare in children)
  • Gross total or near total excision has clearly been shown in many tumor types to improve prognosis.
  • Treatment almost always involves a multidisciplinary team.
  • On the whole, the long term prognosis is better in children than adults.

 

Incidence

The incidence of pediatric brain tumors is roughly 3.3 cases per 100,000 children in North America.

About 3000 children are diagnosed with brain tumors annually in the US.

About 30 children a year in British Columbia are diagnosed with a brain tumor. 

Between 1973 and 1994, there was an increase in the reported incidence of childhood brain tumors.  This coincided with the increased use of MRI imaging of the CNS which is likely to account for the perceived change in incidence.

 

From Canadian Cancer Statistics 2011:

In Canada:

Between 2003 and 2007, central nervous system (CNS) accounted for 16% of childhood cancer cases.  During this time there were a total of 1,039 CNS cancers:

  • 44% were astrocytomas
  • 20% were intracranial and intraspinal embryonal tumors
  • 10% were ependymomas


Approximately 27% of the deaths caused by childhood and youth cancers from 2002
to 2006 were secondary to CNS cancers.

For CNS cancers, the prognosis for astrocytoma (Five year OSP: 81%) was found to be higher than for intracranial and intraspinal embryonal tumors (Five year OSP: 58%). The great majority of astrocytomas in children are low grade.

(OSP = Observed survival proportions)

 

Age-Standardized Incidence and Mortality Rates for Central Nervous System Tumors in Children and Youth (0–19 Years), Canada, 1985–2011:

 

 

 

Age-Related Risk

Children under 5 years of age have the greatest incidence of brain tumors. 

One third of all pediatric brain tumors present before the age of 5, and three-quarters before age 10.

 

Site of Origin

Roughly 60% of all childhood brain tumors are infratentorial and arise in the posterior fossa. 

The most common of these are:

  • Medulloblastoma
  • Low-grade astrocytomas of the cerebellum
  • Ependymomas

 

The frequency of specific types of brain tumors differs by cell type and age.

 

Relative Frequency of Pediatric Brain Tumors:

Relative Incidence of Pediatric Brain Tumors

 

 

Relative Incidence of Common Brain Tumors in Children:

Diagnosis

Relative Frequency

Peak Age Group (years)

Astrocytoma

  • Supratentorial
  • Infratentorial

35%
22%
13%

2-10
>6
2-10

Malignant glioma (anaplastic astrocytoma and glioblastoma multiforme)

8%

<1, >6

Brain stem glioma

8%

3-9

Oligodendroglioma

2%

<6

PNET (Medulloblastoma and supratentorial PNET)

20%

1-10

Ependymoma
   -Supratentorial
   -Infratentorial

8%

3%

5%

 

>6
1-5

Craniopharyngioma

7%

8-14

Pineal region and germ cell tumors

4%

<2, >6

Choroid plexus tumors

2%

<1

Others: ganglioglioma, meningioma, primitive embryonal tumors

<2% each

 

 

 

Summary of incidence characteristics for pediatric brain tumors:

Annual incidence (Canada)

217

Proportion of all childhood neoplasms

20%

Highest risk group

<5 years old

Proportion of cases presented <5 years of age

30%

Proportion of cases presented <10 years of age

75%

Most common site of origin

Posterior fossa

Most common histological subtype

Astrocytoma

 

Prognosis

The overall survival for children with pediatric brain tumors has improved in the past 10 to 20 years and is just over 70%.

This is most likely due to:

  • Improved imaging/diagnosis
  • Multidisciplinary approach
  • Improved therapy
    • Improved neurosurgical techniques and reduced peri-operative mortality
    • Increasingly precise RT
    • More intensive, multi-agent chemotherapy

 

Back to top

Next