The death of Senator John McCain (R-Ariz.) sheds a new light on glioblastoma, a form of brain cancer that the American Brain Tumor Association estimated would be diagnosed in nearly 13,000 people this year.

"Glioblastoma makes up about 60% of what we call primary brain tumors, tumors that start within the brain," said Keith L. Black, MD, chair of the Neurosurgery Department at Cedars-Sinai and a leading expert on the tumor. "It tends to be very aggressive—it strikes people in the prime of their lives, and with the best standard therapy survival is still very short, with median survival of about 24 months."

Black said one of the strongest factors for prognosis and survival is age. Though he did not treat McCain, 81—who was diagnosed with glioblastoma last summer—and had not been briefed on his care, Black said it was not surprising that the disease progressed quickly. "If a patient develops a glioblastoma over age 40, the prognosis is worse, and that just goes up with age," he said. "At 60, 70, 80, the prognosis will be worse."

Glioblastoma generally appears in the brain spontaneously. "Unlike lung cancer, which is associated with risk factors like smoking, we don't know of any clear risk factors associated with a higher risk of having a glioblastoma," Black said. About 5%, he said, may have a genetic component.

The symptoms of a glioblastoma are related to the location of the tumor in the brain. Most common are the onset of seizures in an adult who has not suffered from them previously. "Other symptoms can include headache and changes in anything that is controlled by the brain—the ability to move your arms or legs, developing weakness or numbness, or visual loss and speech difficulty," Black said. The standard treatment for glioblastoma is a combination of surgery, chemotherapy, and radiation.

—Newswise