Optic glioma in children: Turkish experience.

Abstract

e14042 Background: Optic gliomas are the most common tumors of the optic pathway, comprising about 1% of all intracranial tumours. Here we present the clinical characteristics and the outcome of patients with optic glioma at our institution. Methods: Seventy two patients diagnosed and followed up at a pediatric cancer center in Ankara, Turkey between January 1, 2008 and December 31, 2020 were included in this analysis. The clinical features and outcome of patients were recorded from patient files and hospital information system retrospectively. Results: The median age at the time of diagnosis was 3.5 years (4-157 months), the female/male ratio was 1.3. Fourteen children (19%) were asymptomatic and tumors were detected with routine surveillance, and 58 (81%) had symptoms (the most common being proptosis in 16 patients (22%)). The most common site of optic glioma was the intraorbital region (31%). Fourty patients (55%) had neurofibromatosis type 1 (NF-1). Five patients had histopathological diagnoses; 3 pilomyxoid astrocytoma, 2 pilocytic astrocytoma. Children were treated if they had tumor progression on MRI and/or worsening visual acuity. Twenty seven (38%) children were observed without any therapy, 6 patients (8%) received radiation and chemotherapy, 4 patients (5%) received radiation only, and 35 patients (49%) received chemotherapy only. Treatment regimens for the 41 children who received chemotherapy included carboplatin/etoposide (17), cisplatin/etoposide (18), carboplatin/vincristine (5), and temozolomide (1). The 5-year progression-free survival (PFS) and overall survival (OS) were 64% and 90%, respectively with a 31 month median follow-up. The 5 year PFS was significantly lower in patients with optic tract-hypothalamic-chiasmatic involvement (34%) than orbital involvement (83%) (p=0.013). Five year PFS was significantly higher in patients with NF-1 (80%) than patients without NF-1(46%) (p=0.027) and significantly lower in patients diagnosed at <3 years old (37%) (p=0.05). Five patients died of disease, and one died of infection after chemotherapy. Two patients treated with platin (1 carboplatin, 1 cisplatin) developed ototoxicity. One patient with NF-1 developed Moya-Moya disease. Two patients developed multiple pituitary hormone deficiencies and one patient developed precocious puberty during follow-up. No secondary malignancy was observed. Conclusions: The management of optic glioma remains challenging. Although the overall survival for children with this disease is excellent, progression of disease is frequent, particularly in those children without NF-1, younger children and non-orbital tumors. This study from Turkey showed comparable results with high-income countries. Further studies with longer follow-up periods are needed to find appropriate treatment strategies.