A grim diagnosis: Kennedy's brain cancer is worst kind

There are some experimental therapies that researchers are watching closely, including:

_Adding the colon cancer drug Avastin to standard treatment. Avastin chokes off tumors' blood supply, and initial studies suggest it can help shrink gliomas. Whether that helps survival isn't yet known, but Black says even though this use is experimental, more and more specialists are prescribing it right after diagnosis.

_Trying experimental cancer vaccines. Brain tumors often can't be seen by the immune system. So scientists take cells from the surgically removed glioma, put them on the immune cells and give them back to the patient. Small studies at Cedars-Sinai suggest the approach improved two-year survival from 8 percent of glioblastoma patients to 42 percent, Black said. But it's only an option for surgery candidates.