Optic Pathway Glioma: Management and Prognosis in 25 Surgically Treated Cases

Abstract

Gliomas of the optic pathway (OPG) are quite rare. These tumors arise intracranially and account for about 1% of all intracranial tumors. About 85% of OPG present in children under the age of 15. An association with neurofibromatosis 1 (NF1) is well known and occurs in about one-third of all patients with OPG [12]. A benign pilocytic astrocytoma (WHO grade I) is generally found to be associated with NF-1. OPG comprise a broad spectrum of tumor pattern and growth dynamics. They can involve the total length of the optic pathway, and show extreme variation in tumor shape and appearance. The tumor may be located intracranially or intraorbitally within the optic nerve structures (intrinsic growth). Sometimes they reveal a large extrachiasmatic portion compressing or infiltrating adjacent brain structures, especially the hypothalamic region (extrinsic growth). This great variety of findings has made the management of OPG controversial. Treatment modalities include different extents of surgery, [14], radiotherapy [18], and more recently chemotherapy [10]. Other investigators have found no benefit from any kind of treatment [6]. This report reviews of our cases in an attempt to clarify the management and to select relevant prognostic factors which may influence treatment strategies.