Isocitrate dehydrogenase 1 (IDH1) mutations have been discovered to be frequent and highly conserved in secondary glioblastoma multiforme and lower-grade gliomas. Although IDH1 mutations confer a unique genotype that has been associated with a favorable prognosis, the role of the mutated IDH1 enzyme and its metabolites in tumor initiation and maintenance remains unresolved. However, given that IDH1 mutations are homogeneously expressed and are limited solely to tumor tissue, targeting this mutation could potentially yield novel treatment strategies for patients with glioblastoma multiforme.