Variegated Colors of Pediatric Glioblastoma Multiforme: What to Expect?

Abstract

Malignant gliomas account for 35-45% of primary brain tumors; among these glioblastoma multiforme (GBM) is the most common adult brain tumor constituting approximately 85%. Its incidence is quite less in the pediatric population and treatment of these patients is particularly challenging. Exposure to ionizing radiation is the only environmental factor found to have any significant association with GBM. Several genetic alterations associated with GBM in adults have been well documented such as epidermal growth factor receptor amplification, overexpression of mouse double minute 2 homolog also known as E3 ubiquitin-protein ligase, Phosphatase and tensin homolog gene mutation, loss of heterozygosity of chromosome 10p and isocitrate dehydrogenase-1 mutation. However, data on genetic mutations in pediatric GBM is still lacking. Exophytic brain stem gliomas are rare tumors and are usually associated with a poor prognosis. The most effective treatment in achieving long-term survival in such patients, is surgical excision of the tumor and then chemoradiotherapy followed by adjuvant chemotherapy by temozolomide. This schedule is the standard treatment for GBM patients. In view of the rarity of pediatric GBM, we report here a case of pontine GBM in a 5-year-old girl.

Keywords: Brain neoplasms; Glioblastoma; Glioma; Humans; Ionizing radiation; Pons.

Figure 1.

Pre-operative contrast-enhanced magnetic resonance imaging showing a neoplastic process involving the left pons, the left middle cerebellar peduncle including the cerebellopontine angle with exophytic component extending into the mid brain and medulla.

Figure 2.

A) Photomicrograph showing tumor cells (400×); B) photomicrograph showing bizarre multinucleated giant cells, central area of necrosis with focal hemorrhages with peripheral palisading of tumor cells (100×).

Figure 3.

A) Photomicrograph showing immunoexpression of glial fibrillary acidic protein by tumor cells; B) photomicrograph showing tumor cells negative for CD99; C) photomicrograph of Ki-67 immunostaining showing proliferative index of 60%; D) photomicrograph showing tumor cells positive for p53.