NCI Definition: A low-grade (WHO grade II) astrocytic neoplasm. It is characterized by diffuse infiltration of neighboring central nervous system structures. These lesions typically affect young adults and have a tendency for progression to anaplastic astrocytoma and glioblastoma. Based on the IDH genes mutation status, diffuse astrocytomas are classified as IDH-mutant, IDH-wildtype, and not otherwise specified. [1]

Diffuse astrocytomas most frequently harbor alterations in TP53, IDH1, ATRX, TNFAIP3, and PIK3CA [2].

Most Commonly Altered Genes in Diffuse Astrocytoma

TP53 c.217-c.1178 Missense, TP53 c.142-c.212 Missense, TP53 c.1-c.137 Missense, TP53 Mutation, and TP53 Missense are the most common alterations in diffuse astrocytoma [2].

Top Alterations in Diffuse Astrocytoma

Significant Genes in Diffuse Astrocytoma

IDH1 +

IDH2 +

Disease Details

Astrocytoma, Diffuse, Grade II Astrocytic Neoplasm, Grade II Astrocytoma, Grade II Astrocytic Tumor, Low-grade astrocytoma, NOS, WHO Grade II Astrocytoma, ASTROCYTOMA, DIFFUSE, MALIGNANT
WHO Grade II Glioma
Gemistocytic Astrocytoma, Protoplasmic Astrocytoma, and Fibrillary Astrocytoma
OncoTree Name
Diffuse Astrocytoma
OncoTree Code


1. National Cancer Institute. NCI Thesaurus Version 18.11d. https://ncit.nci.nih.gov/ncitbrowser/ [2018-08-28]. [2018-09-21].

2. The AACR Project GENIE Consortium. AACR Project GENIE: powering precision medicine through an international consortium. Cancer Discovery. 2017;7(8):818-831. Dataset Version 4. This dataset does not represent the totality of the genetic landscape; see paper for more information.

3. All assertions and clinical trial landscape data are curated from primary sources. You can read more about the curation process here.