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Kennedy's brain tumor battle shifts to a new phase: radiation, chemo, maybe experimental meds

Kennedy's brain tumor battle shifts to a new phase: radiation, chemo, maybe experimental meds

Sen. Edward M. Kennedy is back home from brain cancer surgery with something he didn't have before: lots of treatment options.
Because his tumor was operable, the 76-year-old senator is a candidate for the most promising treatments _ traditional and experimental _ being used against his dire disease.
Kennedy flew back to Massachusetts on Monday, a week after having much of his tumor removed at Duke University in North Carolina, and will have the next phase of his treatment at Massachusetts General Hospital in Boston.
Now comes the hard part: choosing what to try. Six weeks of radiation and chemotherapy with Temodar are standard, but the tumor nearly always comes back.
"It would be very reasonable" to add an experimental treatment right away, said the American Cancer Society's top doctor, Otis Brawley.
"We do that all the time," agreed Duke neurosurgeon Dr. John Sampson. He was not involved in Kennedy's care but works with doctors who were.
The choices are complex. Picking one treatment often precludes another. For example, brain tumor patients who try the drug Avastin are not eligible to later try an experimental cancer vaccine Sampson helped develop.
That vaccine is only for people who make it through standard chemo and radiation and have a specific gene variant. It's not known if Kennedy does.
The senator's doctors and family have said only that he will get chemo and radiation, which are typically begun after a week or two of rest. The treatments can cause fatigue, brain swelling, nausea, vomiting and hair loss.
Temodar eventually stops working, and patients then try one experimental drug or combo after another.
Participating in three such studies allowed Steve Sigur _ Brawley's daughter's high school math teacher _ to finish out the school year and enjoy his passion for hiking in Colorado, despite having a tumor like Kennedy's.
"All of a sudden, I could live a free life, at least in part," said Sigur, 62, of Atlanta. "I was teaching for most of the past eight, nine months" until suffering a setback two weeks ago.
Most people start with standard care _ radiation five days a week for six weeks, plus daily Temodar. After that, Temodar usually is given in monthly cycles _ the first five of every 28 days _ until patients relapse or side effects prevent them from continuing.
Other options:
_Dose-dense or continuous Temodar. The drug is given 21 out of 28 days at a lower daily dose but a higher total amount. A study of this approach has enrolled more than 1,100 patients, including patients at Mass General, where Kennedy will be treated, and researchers hope to have results by the fall of 2009.
_An experimental vaccine. This prods the immune system to fight the cancer and targets a protein found in roughly half of glioblastoma multiforme tumors, the type many specialists believe Kennedy has. Eligible patients must be stable without tumor progression after the standard six weeks of Temodar.
Two mid-stage studies tried it on a total of 44 patients. One study presented at an American Society of Clinical Oncology conference on the day Kennedy had his surgery reported that patients survive without tumor growth for more than 16 months. There was no comparison group, but six months is typical, Sampson said.
Sampson consults for the vaccine's maker, Celldex Therapeutics, a subsidiary of Avant Immunotherapeutics, and gets licensing fees from the vaccine. A larger, late-stage study is under way at more than 20 sites nationwide, including Boston.
_Experimental drugs. These target signaling pathways that tumors use, and some are already approved to treat other forms of cancer. A mid-stage study of Avastin with or without the chemo drug irinotecan found that nearly half were alive without disease progression at six months versus the 15 percent who typically would be, doctors reported at the oncology conference.
Other experiments are trying cediranib, an Avastin-like drug; Erbitux, which aims at a different cancer pathway; and talampanel, a drug that targets a third tumor mechanism. These are being tested at Mass General, among other places.
_Radio-labeled antibodies. This approach attaches a radioactive "homing device" to connect a drug to the tumor and increase its effectiveness. The treatment is injected into the brain cavity where the tumor was.
_Gliadel wafers. These chemo-coated wafers are placed in the brain at time of surgery and slowly release medicine, avoiding the problem of getting it across the blood-brain barrier.
"I'm not aware if the senator got those or not" when he had his operation, Sampson said.
It would be wrong to assume that radiation and Temodar are the only choices for initial therapy, he said. Kennedy reportedly had a team of doctors from Duke, Mass General and the federal government advising him on his options.
"At the end of the day, people have different perspectives, and different trials have different risks," Sampson said.
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Updated : 2021-04-20 09:04 GMT+08:00