astrocytoma
Pronunciation: AS-troh-sy-TOH-mah
Primary brain tumor arising from astrocytes, classified by WHO grade and molecular features including IDH mutation status.
Full Definition
A type of primary central nervous system tumor that develops from astrocytes, star-shaped glial cells that provide structural and metabolic support to neurons. Astrocytomas are classified according to WHO grading (I-IV) based on histological features including cellular atypia, mitotic activity, microvascular proliferation, and necrosis. Modern classification incorporates molecular markers, particularly IDH mutation status, which significantly influences prognosis and treatment strategies. Treatment typically involves surgical resection when feasible, followed by radiation therapy and chemotherapy based on tumor grade and molecular profile.
Usage
Usage note: Current WHO classification emphasizes molecular characteristics; glioblastoma is a grade IV astrocytoma.
In Context
- "The pathology report confirmed a grade II astrocytoma with IDH1 mutation, indicating a more favorable prognosis." — multidisciplinary conference
- "Diffuse astrocytoma in eloquent brain regions may require awake craniotomy for safe maximal resection." — surgical planning