PURPOSE OF REVIEW: Evolving molecular data have led to a new and advanced grading system of anaplastic glioma. In everyday practice, physicians have to translate evidence from old clinical trials into evidence meeting the reclassified tumor types. RECENT FINDINGS: New biomarkers allow the identification of anaplastic glioma with relatively poor prognosis and with prognosis similar to glioblastoma. An update with molecular analysis of the phase 3 CATNON trial demonstrates the benefit of adjuvant temozolomide (TMZ) to be dependent on the mutational status of isocitrate dehydrogenase. In the ongoing debate on the optimal chemotherapy regimen, a large retrospective study suggesting a better tumor control with vincristine (PCV) as compared to TMZ is added to the evidence. The best timing for treatment of anaplastic astrocytoma also remains a matter of controversy. A recent study shows that even in selected patients with anaplastic glioma with foci of malignant tumor following (sub)total resection, postponement of medical treatment can be considered. SUMMARY: In clinical practice, the trade-off between efficacy and (acute and long-term) toxicity of treatments needs to be re-evaluated for the newly (molecularly) defined entities. Updates from past clinical trials on anaplastic glioma with molecular analysis and subgroup analyses are needed to further guide treatment decisions.