glioblastoma multiforme
Pronunciation: glee-oh-blas-TOH-mah MUL-ti-for-may
Aggressive primary brain tumor arising from glial cells, representing the most malignant form of glioma.
Full Definition
Glioblastoma multiforme (GBM) is a WHO Grade IV astrocytoma and the most aggressive primary brain tumor in adults. The tumor is characterized by rapid growth, extensive infiltration into surrounding brain tissue, and resistance to treatment. Histologically, GBM demonstrates pleomorphism, mitotic activity, microvascular proliferation, and necrosis. The term 'multiforme' refers to the varied cellular appearance under microscopy. Current classification emphasizes molecular markers including IDH mutation status and MGMT promoter methylation, which influence prognosis and treatment planning.
Usage
Usage note: Modern practice emphasizes molecular classification; include IDH and other molecular markers when available.
In Context
- "Pathology confirmed glioblastoma multiforme with wild-type IDH status." — Neuropathology report
- "The patient underwent gross total resection of a right temporal glioblastoma multiforme." — Operative neurosurgery note