Monarch Disease Ontology term MONDO_0016696 (anaplastic oligodendroglioma) is a WHO grade III oligodendroglioma with focal or diffuse malignant morphologic features (prominent nuclear pleomorphism, mitoses, and increased cellularity). Also known as: WHO grade III oligodendroglial neoplasm, WHO grade III oligodendroglial tumor, WHO grade III oligodendroglial tumour, malignant oligodendroglioma, oligodendroglioma, anaplastic, malignant, oligodendroglioma, malignant, undifferentiated oligodendroglioma.