Treatment results of low-grade gliomas in children (a retrospective data analysis)

Children with low-grade gliomas (except for brain stem gliomas) have a good prognosis, 80 to 90 % of them being long time survivors. Their optimal management depends primarily on the anatomical location of the tumour and the patient age. We present a retrospective analysis of 108 children treated at our institution according to SIOP CNS 9702 study between 1998 and 2006, The median age at diagnosis was 5.5 years, with the prevalence of boys (58.3 %). The distribution of histological types was as follows: pilocytic astrocytoma (46.3 %), fibrillary astrocytoma (20.4 %), and oligodendroglioma (5.6 %). In the whole cohort, the 5-year overall survival (OS5) rate was 96.2 %, and the 5-year event-free survival (EFS5) rate was 83.8 %. EFS rate was 90 % for the gross total resection group, and median EFS for incomplete surgery was 77.4 months (p = 0.007). Unfavourable locations are the diencephalon, metastatic spread and multiple structure affection, with a median EFS of 78.8 months (p = 0.005). 36 children were treated with chemotherapy with the EFS rate of 60 % and PFS rate of 50 %. Only 4 children died, of whom 3 of progression or relapse. We have proven 2 factors with a significant impact on the survival indicators: the extent of resection and tumour localization. Chemotherapy allows postponing radiotherapy for a part of children. The risk subgroups for which new therapeutic options are needed are mainly inoperable tumours of diencephalon.