Anaplastic Astrocytoma

**Semantic type:** Neoplastic Process

**Definition:** A diffusely infiltrating, WHO grade 3 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)

**Synonyms:** - Anaplastic astrocytoma - Astrocytoma, anaplastic - Grade 3 Astrocytic Neoplasm - Grade 3 Astrocytic Tumor - Grade 3 Astrocytoma - Grade III Astrocytic Neoplasm - Grade III Astrocytic Tumor - Grade III Astrocytoma - High Grade Astrocytoma - High-Grade Astrocytoma - High-grade astrocytoma, NOS - Malignant Astrocytoma