Glioblastoma

Glioblastoma, previously known as glioblastoma multiforme (GBM), is the most aggressive and most common type of cancer that originates in the brain, and has a very poor prognosis for survival. Initial signs and symptoms of glioblastoma are nonspecific. They may include headaches, personality changes, nausea, and symptoms similar to those of a stroke. Symptoms often worsen rapidly and may progress to unconsciousness.

The cause of most cases of glioblastoma is not known. Uncommon risk factors include genetic disorders, such as neurofibromatosis and Li–Fraumeni syndrome, and previous radiation therapy. Glioblastomas represent 15% of all brain tumors. They are thought to arise from astrocytes. The diagnosis typically is made by a combination of a CT scan, MRI scan, and tissue biopsy.

There is no known method of preventing the cancer. Treatment usually involves surgery, after which chemotherapy and radiation therapy are used. The medication temozolomide is frequently used as part of chemotherapy. High-dose steroids may be used to help reduce swelling and decrease symptoms. Surgical removal (decompression) of the tumor is linked to increased survival, but only by some months.

Despite maximum treatment, the cancer almost always recurs. The typical duration of survival following diagnosis is 10–13 months, with fewer than 5–10% of people surviving longer than five years. Without treatment, survival is typically three months. It is the most common cancer that begins within the brain and the second-most common brain tumor, after meningioma, which is benign in most cases. About 3 in 100,000 people develop the disease per year. The average age at diagnosis is 64.