Central nervous system tumors are the most common solid cancer in children < 15 years old and are the leading cause of childhood death due to cancer. Diagnosis is typically by imaging (usually MRI) and biopsy. Treatment may include surgical resection, chemotherapy, targeted therapy, or radiation therapy.
Central nervous system (CNS) tumors are the leading cause of cancer mortality in children, accounting for 25% of deaths (1). The cause of most childhood central nervous system tumors is unknown, but 2 established risk factors are ionizing radiation (eg, high-dose cranial irradiation) and specific genetic syndromes (eg, neurofibromatosis).
The most common central nervous system tumors in children are (in order)
Reference
1. Siegel RL, Giaquinto AN, Jemal A. Cancer statistics, 2024 [published correction appears in CA Cancer J Clin. 2024 Mar-Apr;74(2):203]. CA Cancer J Clin. 2024;74(1):12-49. doi:10.3322/caac.21820
Symptoms and Signs of CNS Tumors in Children
Increased intracranial pressure resulting from obstructive hydrocephalus is the cause of the most common manifestations, which include
Headache
Nausea and vomiting
Irritability
Lethargy
Changes in behavior
Gait and balance disorders
Other common symptoms are related to tumor location, including vision loss and seizures.
Diagnosis of CNS Tumors in Children
MRI
Biopsy
MRI is the imaging test of choice because it provides more detailed images of parenchymal tumors and can detect tumors within the posterior fossa, subarachnoid spaces, and the arachnoid and pia mater. CT may be done but is less sensitive and less specific.
Once imaging confirms the presence of a brain mass, a biopsy is needed in a majority of cases to confirm the diagnosis and to determine tumor type and grade. The World Health Organization (WHO) has created a commonly used classification system (1) that includes molecular and histologic information to further classify central nervous system tumors.
Once a diagnosis is made and tumor histology is determined, staging and risk assessment are then performed. Staging (determination of whether the tumor has spread) includes an MRI of the entire spine, a lumbar puncture for cerebrospinal fluid cytology, and a postoperative MRI to assess for any residual tumor. Risk assessment is based on age, degree of residual tumor, molecular findings, and evidence of spread of disease.
Diagnosis reference
1. Louis DN, Perry A, Wesseling P, et al. The 2021 WHO Classification of Tumors of the Central Nervous System: a summary. Neuro Oncol. 2021;23(8):1231-1251. doi:10.1093/neuonc/noab106
Treatment of CNS Tumors in Children
Surgical resection
Radiation therapy, chemotherapy, targeted therapy, or a combination
Treatment approach depends on the diagnosis, grade, stage, and risk assessment. In general, after initial surgery, radiation therapy, chemotherapy, targeted therapy, or a combination may be required.
Entry into a clinical trial, if available, should be considered for all children with a CNS tumor. Optimal treatment requires a multidisciplinary team of pediatric oncologists, pediatric neuro-oncologists, pediatric neurosurgeons, neuropathologists, neuroradiologists, and radiation oncologists who have experience treating CNS tumors in children. Because radiation therapy for CNS tumors is technically demanding, children should be sent to centers that have experience in this area if possible.
More Information
The following English-language resource may be useful. Please note that THE MANUAL is not responsible for the content of this resource.
World Health Organization (WHO): WHO Classification of Tumors of the Central Nervous System, fifth edition (2021)
