Behind the Tumor: Glioblastoma (GBM)

Glioblastoma multiforme (GBM) is the most common type of malignant (cancerous) brain tumor in adults. Cancer cells in GBM tumors rapidly multiply. The cancer can spread into other areas of the brain as well. Rarely, the cancer spreads outside the brain to other parts of the body. Glioma tumors like GBM start in glial cells. Glial cells are vital to nerve cell function. GBMs specifically form in glial cells called astrocytes. GBMs are the fastest-growing astrocytoma (tumor that forms in astrocytes). Types Healthcare providers use a grading system from 1 to 4 to indicate brain tumor growth.