Natural history and outcome of optic pathway gliomas in children

Abstract

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.