The natural history of sporadic optic gliomas was compared with that of optic gliomas associated with neurofibromatosis type 1 (NF1) in a study using a Children’s Tumor Registry (CTR) and an NF1 Database (NF1DB) at St Mary’s Hospital, Manchester, UK. A total of 52 cases were identified over a period of 41 years. Of 34 whose natural history was available, 31 were symptomatic. Mean ages of presentation were 4.5 and 5.1 years for NF1 and sporadic cases, respectively. Visual impairment was the presenting complaint in 22, 7 being blind in at least one eye. Recurrence occurred in 12. Overall mortality (47% among NF1 patients and 44% in sporadic cases) and 5 and 10 year survival rates (77% and 67% respectively) were similar in the two groups, but fewer NF1 patients died as a direct result of the optic glioma. Only NF1 optic glioma cases were at risk of developing a second CNS tumor. Five children (29%) with NF1 developed second primary intracranial tumors between 7 and 32 years after initial treatment. Two had received initial radiotherapy. [1]

COMMENT. Optic gliomas account for less than 5% of childhood brain tumors. The prevalence of neurofibromatosis in patients with optic gliomas in this study is 50% (18/36); estimates range from 10% to 70% in previous cited reports. The prevalence of symptomatic optic glioma occurring in the the above NF1 database patients is 5%. NF1 related optic gliomas are less aggressive and less likely to recur than sporadic cases. Serial eye exams are advised up to 6 years of age, and identified cases should be followed through adult life to rule out development of a second CNS tumor. Sporadic optic gliomas should be treated aggressively, and radiotherapy for NF1 optic gliomas requires clarification.