IDH1 and central nervous system cancer: In a multi-institutional retrospective analysis of 78 pediatric patients with IDH1/2 mutated gliomas including 45 patients with low grade astrocytoma, the 5Y PFS of patients with gross total resection (GTR) was 45.7% with median PFS of 4.4 years compared to 5Y PFS of patients with subtotal resection (STR) of biopsy of 41% with median PFS of 4.7 years (21).