Diffuse paediatric cerebellar glioma: two identical imaging phenotypes of an extremely rare entity with disparate pathology

Although the posterior fossa is a common location for paediatric brain tumours [1], diffuse glioma isolated to the cerebellum is an extremely rare imaging entity. Only two cases of isolated diffuse paediatric cerebellar glioma have been reported in the English language to the best of our knowledge [2, 3], and only one of these cases had a similar imaging phenotype to our cases [3]. Although somewhat similar to Lhermitte-Duclos (dysplastic gangliocytoma of the cerebellum), the appearances are distinct from other neoplastic entities of the paediatric posterior fossa. Clinical presentation and neurological examination findings are vital however to help differentiate other diffuse pathologies involving the cerebellum such as rhombencephalitis. Presented here are two diffuse cerebellar gliomas in children under the age of 3 with near identical imaging phenotypes demonstrating differing histological and molecular genetic profiles.

Automated summary

Although paediatric brain tumours often occur in the posterior fossa, isolated diffuse gliomas in the cerebellum are extremely rare imaging findings. Only two cases of isolated diffuse paediatric cerebellar gliomas have been reported in English literature, and only one of these cases had similar imaging characteristics to our cases. These gliomas are distinct from other neoplastic entities in the paediatric posterior fossa, such as Lhermitte-Duclos. Clinical presentation and neurological examination are crucial in distinguishing these diffuse cerebellar pathologies from conditions like rhombencephalitis. This report presents two cases of diffuse cerebellar gliomas in children under 3 years old, with nearly identical imaging phenotypes but different histological and molecular genetic profiles.