Major study points to better management for optic glioma

Children with optic gliomas should benefit from better management after a study has established how different gliomas behave. Aggressive treatment is recommended for sporadic gliomas and early monitoring for gliomas associated with neurofibromatosis type 1 (NF1).

Seventeen cases in the study were of optic glioma associated with NF1 and 17 were of sporadic optic glioma. Thirty one cases had an array of symptoms. Significantly more cases of sporadic glioma had visual symptoms (94% versus 47%) and died from their glioma (six versus two cases).

Diagnosis was generally based on histological findings whereas some cases with NF1 were identified radiologically. Surgery was used twice as often as radiological treatment for both gliomas. Absolute mortality and five and 10 year survival were equivalent for both types, but a primary brain tumour developed in five cases of NF1, in three of which treatment for the glioma had been radiological.

The study was a retrospective case note study of optic glioma identified from the North West Regional NF1 Database and Manchester Children’s Tumour Registry from records spanning more than 41 years. It was based on 34 cases with sufficient details of the natural history of the condition.

NF1 is a common genetic disorder affecting 1 in 3000, and optic glioma is its most common complication, with a prevalence of 11–19%. There are conflicting accounts of the natural history of optic gliomas and suggestions that gliomas in NF1 are benign and screening is unnecessary, even that NF1 protects children with optic glioma.