Pediatric glioma

Abstract

Tumors of the central nervous system (CNS) are the most common solid neoplasms in children. About 5% of all CNS tumors occur in the age group 0–14 years. Gliomas constitute approximately half of tumors in children, majority being low grade gliomas (LGG). The high grade gliomas (HGG) include ependymomas, anaplastic astrocytoma (AA), anaplastic oligodendroglioma (AO), mixed gliomas—oligoastrocytoma, and glioblastoma (GBM) depending upon the astrocytic cell of origin (Louis et al. 2007). While HGGs represent one of the most common CNS tumors among adults, they comprise only 20% of all primary CNS tumors in the pediatric population. GBMs comprise only about 3% of all pediatric CNS tumors (Ostrom et al. 2015). Based on the recent CBTRUS data, HGG are the third most common histology in 0–4 years age group and second most common in 5–14 years age group. Age-adjusted incidence rates of HGG are 0.9 per 100,000 in 0–4 years age group and 0.5–0.9 per 100,000 in 5–14 years age group. Among HGG, supratentorial location constitutes 6–12% of all primary pediatric CNS tumors (Pollack 1994). If brainstem gliomas are excluded, then supratentorial is the most common location. Most supratentorial HGGs are located in cerebral hemispheres—35–50%, followed by 20–30% located in thalamus and basal ganglia (Fangusaro 2012).