Surgical Treatment of Optic Pathway Hypothalamic Gliomas

Abstract

This paper provides an overview of optic pathway hypothalamic gliomas (OPHGs), neoplastic lesions that are mainly low-grade gliomas with predominance of pilocytic astrocytomas. They typically occur more frequently in children, but arise also in adults. While some tumors affect the optic nerve alone, the majority of them invade the hypothalamus and optic chiasm as well as adjacent structures. According to the pertinent literature, most authors consider extensive or curative tumor resection not feasible because of high risk for visual loss or severe hypothalamic side effects. Therefore, radiochemotherapy is a widely used modality to treat these challenging lesions. The authors of the present article describe a different strategy of selecting and treating surgically patients with OPHG. Similar to their management of low-grade gliomas in other intracranial location, they have treated a number of OPHGs microsurgically with curative intention. The present patient series comprises 56 individuals (42 pediatric and 14 adult patients). The authors achieved microsurgical gross total (99-100% tumor volume reduction) and near total tumor resection (90-98% volume reduction) in 42 patients (75.0%). There was no surgical mortality, and the rate of complications was low. Postoperatively, the patient's visual and endocrine function remained either intact or at a very satisfactory level in the vast majority of cases. These results differ from those found in previous publications dealing with OPHGs. In the author's experience, proper patient selection played an important role in achieving a good outcome. They conclude that microsurgical management should be considered an important part of the treatment plan in OPHGs. Patients should undergo surgery in an early stage before irreversible symptoms have occurred, and gross total tumor resection should be attempted in well-selected cases. Intentional partial OPHG resection and repeat surgery may help prolonging the symptom-free and tumor progression-free intervals.

Keywords: Hypothalamus; Optic nerve tumor; Optic pathway hypothalamic glioma; Surgical treatment.