Natural history and outcome of optic pathway gliomas in children.

The optimal management of optic pathway gliomas (OPGs) is complicated by their variable natural history, the association with neurofibromatosis type 1 (NF1) and difficulties in defining progression and response to treatment. This study is a retrospective review of all children presenting to a single institution with an OPG between 1990 and 2004. Of the 133 children included, 78 (59%) had NF1; 87 (71 NF1) were observed initially, of whom 23 (11 NF1) subsequently required treatment. Forty-six patients received immediate treatment. Initial treatment, without or with an observation period, comprised chemotherapy alone (32, 11 NF1); debulking + chemotherapy (15, 4 NF1); gross total resection (6); radiotherapy (2); debulking + radiotherapy (3); and debulking only (12, 3 NF1). Overall, 16 patients were irradiated during the study period. Four children died (overall survival at 5 and 10 years was 97.6% and 94.6% for those who required treatment). Progression-free survival (PFS) for the 69 patients who needed treatment was 48%. There was no difference in PFS between chemotherapy versus chemotherapy + debulking or debulking alone. PFS for the NF1 patients who required treatment was similar to that of non-NF1 patients. Mean follow-up time was 9.0 (range 0.6-18.0, median 8.6) years. The study confirms the complexity of OPGs and that NF1 is a major determinant of the resultant behavior of the tumor.