This cancer treatment information summary provides an overview of the diagnosis, classification, treatment, and prognosis of childhood brain stem gliomas.

The National Cancer Institute provides the PDQ pediatric cancer treatment information summaries as a public service to increase the availability of evidence-based cancer information to health professionals, patients, and the public. These summaries are updated regularly according to the latest published research findings by an Editorial Board of pediatric oncology specialists.

In recent decades, dramatic improvements in survival have been achieved for children and adolescents with cancer. Childhood and adolescent cancer survivors require close follow-up because cancer therapy side effects may persist or develop months or years after treatment. Refer to the PDQ Late Effects of Treatment for Childhood Cancer for specific information about the incidence, type, and monitoring of late effects in childhood and adolescent cancer survivors.

Primary brain tumors are a diverse group of diseases that together constitute the most common solid tumor of childhood. Brain tumors are classified according to histology, but tumor location and extent of spread are important factors that affect treatment and prognosis. Immunohistochemical analysis, cytogenetic and molecular genetic findings, and measures of mitotic activity are increasingly used in tumor diagnosis and classification.

The classification of childhood brain tumors is based not only on histology, but also on location. Tumors are classically categorized as being infratentorial, sellar or suprasellar, or cortical based. Common infratentorial (posterior fossa) tumors include the following:

1. Cerebellar astrocytomas (usually pilocytic but also fibrillary and, less frequently, high grade).
2. Medulloblastomas (primitive neuroectodermal tumors [PNET]).
3. Ependymomas (cellular, papillary, clear cell, tanycytic, or anaplastic).
4. Brain stem gliomas are typically diffuse intrinsic pontine gliomas or diffuse intrinsic high-grade tumors that are diagnosed neuroradiographically without biopsy. Focal, tectal, and cervicomedullary tumors are generally low-grade tumors.
5. Atypical teratoid/rhabdoid tumors (AT/RT).

Tumors that occur supratentorially include the following:

1. Low-grade cerebral hemispheric astrocytomas (grade 1 [pilocytic] or grade 2).
2. High-grade or malignant astrocytomas (anaplastic astrocytomas, glioblastoma multiforme [grade 3 or grade 4]).
3. Mixed gliomas (low grade or high grade).
4. Oligodendrogliomas (low grade or high grade).
5. Primitive neuroectodermal tumors (including cerebral neuroblastomas, pineoblastomas, ependymoblastomas).
6. AT/RT.
7. Ependymomas (cellular or anaplastic).
8. Meningiomas.
9. Choroid plexus tumors (papillomas and carcinomas).
10. Pineal parenchymal tumors (pineocytomas or mixed pineal parenchymal tumors).
11. Neuronal and mixed neuronal glial tumors (gangliogliomas, desmoplastic infantile gangliogliomas, dysembryoplastic neuroepithelial tumors).
12. Metastasis (rare) from extraneural malignancies.

In addition to those tumors that occur supratentorially, other tumors that most commonly occur in the sellar or suprasellar region are:

1. Craniopharyngiomas.
2. Diencephalic astrocytomas (central tumors involving the chiasm, hypothalamus, and/or thalamus) that are generally low grade (including astrocytomas, grade 1 [pilocytic] or grade 2).
3. Germ cell tumors (germinomas and nongerminomatous).

Important general concepts that should be understood by those caring for a child with a brain tumor include the following:

1. Selection of an appropriate therapy can only occur if the correct diagnosis is made and the stage of the disease is accurately determined.
2. Children with primary brain tumors represent a major therapy challenge that, for optimal results, requires the coordinated efforts of pediatric specialists in fields such as neurosurgery, neuropathology, radiation oncology, pediatric oncology, neuro-oncology, neurology, rehabilitation, neuroradiology, endocrinology, and psychology, who have special expertise in the care of patients with these diseases.[1,2,3]
3. More than one half of children diagnosed with brain tumors will survive 5 years after diagnosis. In some subgroups of patients, an even higher rate of survival and cure is possible. Each child’s treatment should be approached with curative intent, and the possible long-term sequelae of the disease and its treatment should be considered before therapy begins.
4. For most childhood brain tumors, the optimal treatment regimen has not been determined. Children who have brain tumors should be considered for enrollment in clinical trials when an appropriate study is available. Such clinical trials are being carried out by institutions and cooperative groups.
5. Guidelines for pediatric cancer centers and their role in the treatment of pediatric patients with cancer have been outlined by the American Academy of Pediatrics.[4]
6. The cause of most childhood brain tumors remains unknown.[5,6]