Oligodendrogliomas in children.

Oligodendrogliomas are rare central nervous system (CNS) tumors in children. The purpose of this study was to identify prognostic factors for progression free survival (PFS) and overall survival (OS) in pediatric patients with oligodendrogliomas. We retrospectively analyzed clinical data on 37 pediatric patients with oligodendroglial tumors treated at Washington University. Kaplan-Meier method was used to calculate survival rates. Log-rank was used to detect the difference between survival curves. The median age was 11.1 years (range 10 months-18 years), and median follow-up was 4.5 years (range 2 months-30.5 years). The 5-year PFS and OS were 66.4 and 93.4%, respectively. Mixed histology was associated with worse OS compared to patients with pure oligodendroglioma, 5-year OS 77.6 versus 100% (P < 0.01). Patients who underwent gross total resection (GTR) experienced an improved 5-year PFS of 100% compared to 28.8% (P = 0.03) in patients treated with subtotal resection (STR) or biopsy alone. Age >3 years at diagnosis correlated with improved 5-year PFS, 33.3 versus 69.8% (P = 0.01). Neither post-operative chemotherapy nor radiation therapy correlated with improved outcome. GTR and age >3 years at diagnosis remained significant for improved PFS on multivariate analysis. There were no factors correlated with improved overall survival on multivariate analysis. Pediatric oligodendroglial tumors are associated with excellent OS; however, a third of patients developed progressive disease. Our data demonstrate that patients with less than GTR and <3 years at diagnosis are at increased risk for progression and may benefit from more aggressive therapy.