Accordingly, the poor prognosis associated with increasing amount of peri-tumoural edema supports the need to reduce microvascular proliferation when treating high-grade gliomas.[30] Third, we found that in patients with IDH1-R132H negative tumours, a mitotic index greater than 5 / mm2 was associated with a lower rate of death at 12 months. This evidence concerns the gene IDH1 and neoplasm.