General Information

Incidence and Molecular Determinants

The PDQ childhood brain tumor treatment summaries are organized primarily according to the World Health Organization classification of nervous system tumors.[1,2] For a full description of the classification of nervous system tumors and a link to the corresponding treatment summary for each type of brain tumor, refer to the PDQ summary on Childhood Brain and Spinal Cord Tumors Treatment Overview.

Dramatic improvements in survival have been achieved for children and adolescents with cancer. Between 1975 and 2002, childhood cancer mortality has decreased by more than 50%.[3] 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 summary 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.

Childhood ependymoma comprises approximately 9% of all childhood brain tumors representing approximately 200 cases per year in the United States.[4,5]

Molecular determinants of outcome for ependymomas are just being identified. Studies have identified numerous chromosomal aberrations and related molecular genetic changes. Gain of 1q25, overexpression of EGFR, hTERT expression, high levels of nucleolin, activation of the Notch pathway or Tenascin C, and others have been related to poorer prognosis.[6-12] In contrast, gains of 9, 15q, and 18, and loss of chromosome 6 were associated with improved prognosis.[13]

1. Louis DN, Ohgaki H, Wiestler OD, et al., eds.: WHO Classification of Tumours of the Central Nervous System. 4th ed. Lyon, France: IARC Press, 2007. 
   
   
2. Louis DN, Ohgaki H, Wiestler OD, et al.: The 2007 WHO classification of tumours of the central nervous system. Acta Neuropathol 114 (2): 97-109, 2007.  [PUBMED Abstract]
   
   
3. Smith MA, Seibel NL, Altekruse SF, et al.: Outcomes for children and adolescents with cancer: challenges for the twenty-first century. J Clin Oncol 28 (15): 2625-34, 2010.  [PUBMED Abstract]
   
   
4. Gurney JG, Smith MA, Bunin GR: CNS and miscellaneous intracranial and intraspinal neoplasms. In: Ries LA, Smith MA, Gurney JG, et al., eds.: Cancer incidence and survival among children and adolescents: United States SEER Program 1975-1995. Bethesda, Md: National Cancer Institute, SEER Program, 1999. NIH Pub.No. 99-4649., Chapter 3, pp 51-63. Also available online. Last accessed November 02, 2012. 
   
   
5. Central Brain Tumor Registry of the United States.: Statistical Report: Primary Brain Tumors in the United States, 1997-2001. Hinsdale, Ill: Central Brain Tumor Registry of the United States, 2004. Also available online. Last accessed November 02, 2012. 
   
   
6. Tabori U, Ma J, Carter M, et al.: Human telomere reverse transcriptase expression predicts progression and survival in pediatric intracranial ependymoma. J Clin Oncol 24 (10): 1522-8, 2006.  [PUBMED Abstract]
   
   
7. Mendrzyk F, Korshunov A, Benner A, et al.: Identification of gains on 1q and epidermal growth factor receptor overexpression as independent prognostic markers in intracranial ependymoma. Clin Cancer Res 12 (7 Pt 1): 2070-9, 2006.  [PUBMED Abstract]
   
   
8. Pezzolo A, Capra V, Raso A, et al.: Identification of novel chromosomal abnormalities and prognostic cytogenetics markers in intracranial pediatric ependymoma. Cancer Lett 261 (2): 235-43, 2008.  [PUBMED Abstract]
   
   
9. Preusser M, Heinzl H, Gelpi E, et al.: Ki67 index in intracranial ependymoma: a promising histopathological candidate biomarker. Histopathology 53 (1): 39-47, 2008.  [PUBMED Abstract]
   
   
10. Tabori U, Wong V, Ma J, et al.: Telomere maintenance and dysfunction predict recurrence in paediatric ependymoma. Br J Cancer 99 (7): 1129-35, 2008.  [PUBMED Abstract]
    
    
11. Puget S, Grill J, Valent A, et al.: Candidate genes on chromosome 9q33-34 involved in the progression of childhood ependymomas. J Clin Oncol 27 (11): 1884-92, 2009.  [PUBMED Abstract]
    
    
12. Ridley L, Rahman R, Brundler MA, et al.: Multifactorial analysis of predictors of outcome in pediatric intracranial ependymoma. Neuro Oncol 10 (5): 675-89, 2008.  [PUBMED Abstract]
    
    
13. Korshunov A, Witt H, Hielscher T, et al.: Molecular staging of intracranial ependymoma in children and adults. J Clin Oncol 28 (19): 3182-90, 2010.  [PUBMED Abstract]