A Rare Case of Giant Congenital/Infant-type Hemispheric Glioma Harboring Concomitant ALK and EGFR Alteration

Infant-type hemispheric glioma is a subtype of pediatric high-grade glioma that is seen among those under the age of 3-5 years and congenital infant-type hemispheric gliomas are another subtype which is seen among those under 6 months of age. The molecular features and overall survival of infant-type hemispheric gliomas are distinct from those of pediatric and adult high-grade gliomas. The present study reports a fraternal twin case of a giant hemispheric infant-type hemispheric glioma diagnosed at the age of 2 months and treated with gross total resection. Even though the Ki-67 proliferative index of the tumor was 70%, she has been surviving for 4 years. After molecular analysis, the first case of infant-type hemispheric glioma that had concurrent <i>echinoderm microtubule-associated protein-like 4::anaplastic lymphoma kinase</i> gene fusion and an A269V point mutation on exon 7 in <i>epidermal growth factor receptor</i> gene was identified. Among <i>echinoderm microtubule-associated protein-like 4::anaplastic lymphoma</i> kinase gene fusion cases, the present study presents a rare twin case of giant infant-type hemispheric glioma that has a long recurrence-free survival without radiation or targeted therapy. In contrast, the neurocognitive test results of this case at the age of 4 years corresponded to 12-15 months of age.