IDH1 and neoplasm: Tumor characteristics (type or grade, p = 0.29 and 0.59, respectively), molecular mutations (MGMT methylation, p = 0.48; IDH1, p = 0.89; IDH2, p = 0.49), leptomeningeal and corpus callosum involvement (p = 0.79 and 0.20, respectively), Ki-67 (p = 0.40) and the placement of a lumbar drain (p = 0.50) did not show any relationship with entering the ventricle.