umls-concept:C0334579 | skos:definition | NCI: A malignant neoplasm of the brain or spinal cord originating from astrocytes, exhibiting poor differentiation (anaplasia).,NCI: A diffusely infiltrating, WHO grade III astrocytoma with focal or dispersed anaplasia, and a marked proliferative potential. It may arise from a low-grade astrocytoma, but it can also be diagnosed at first biopsy, without indication of a less malignant precursor lesion. It has an intrinsic tendency for malignant progression to glioblastoma. (WHO) | lld:umls |