It's standard practice, so areas that control critical functions aren't damaged, experts say
TUESDAY, June 3 (HealthDay News) -- Sen. Edward Kennedy certainly was heroic as he underwent surgery Monday for a malignant brain tumor while partially awake. But he was no more a superhero than other men and women who suffer from the same condition and are faced with the same type of procedure to remove their cancer.
Experts say this type of brain surgery, when the patient is conscious for at least part of the operation, is not uncommon.
"It's specialized for tumor surgeons, but it's highly warranted in this type of tumor and would be considered the standard of care," said Dr. John S. Yu, director of surgical neuro-oncology at Cedars-Sinai Medical Center in Los Angeles.
"When the tumor is very close to very critical brain areas, such as language or movement, a lot of surgeons will choose to do this procedure aware," added Dr. Walter Jean, associate professor of neurosurgery at Georgetown University Hospital, in Washington, D.C. "You have to have a big enough center that the surgeon is comfortable with this. Certain centers do it more than others."
And incredibly strange as it may seem, keeping patients awake -- or at least partially awake for part of the procedure -- is critical, so crucial brain functions aren't destroyed.
Equally strange, the actual brain does not have the ability to feel.
"The brain itself is not sensitive to touch," said Dr. Eugene S. Flamm, professor and chairman of the department of neurosurgery at Montefiore Medical Center and Albert Einstein College of Medicine in New York City. "It controls all our sensation. You can manipulate the brain and do what you have to do in the brain without the patient being aware of it."
But the patient isn't awake throughout the whole surgical procedure and certainly not while the scalp and skull are being opened or closed -- these areas can feel pain, as anyone who has hit their head on a sharp edge can attest.
"The only painful part of the procedure is when you enter the skin and bone, so the patient is asleep," Yu confirmed.
Patients are awakened from their sedated state, at least somewhat, while the surgeons determine which parts of the tumor can be safely removed without damaging vital nerve centers that control functions such as speech, cognition and movement. During this phase, the patient's head is completely immobilized in a rigid frame, while the rest of the body just lays on a gurney, Yu said.
During this awake period (lasting perhaps 30 to 40 minutes, according to Yu), doctors essentially "map" the brain, stimulating different areas with electronic probes to see how the patient responds. Each person's brain is structured a bit differently, so what works for one patient may not work for the next.
The parietal lobe of the brain, where Sen. Kennedy's tumor was located, is involved with speech, so that appears to have been the main concern of his team of specialists. But the front part of the parietal area also abuts the sensory cortex, which is connected to motor function, Yu explained.
"The only way you can really test speech enough to avoid the critical speech areas is by waking up the patients and having them perform certain speech tasks, such as naming objects and responding to questions," Yu said.
"What you don't want to do is take something out and say, 'Now, can you move your hand?' " added Flamm. "You want an early warning system."
Areas that control critical functions are then physically tagged with a sterile piece of paper and also located on an MRI, Georgetown's Jean said.
It's not unusual for the entire operation to last four to eight hours, said Dr. Paul Graham Fisher, the Beirne Family Director of Neuro-Oncology at Packard Hospital at Stanford University. Even so, surgeons are never able to remove all of the malignancy.
"These tumors are very infiltrative," Yu said. "The idea is to get as much of it as possible, particularly those you can see on the MRI. Then the parts you can't see with MRI are treated with conventional therapies like radiation and chemotherapy."
"The data say clearly that if you can resect [cut away] a substantial part of the tumor, it's much better than doing a biopsy alone," Fisher said. "It gives better quality of life, more time to the patient, and it also allows you to try other options. It opens other doors."
After surgery, patients are usually asked to undergo chemotherapy and radiation.
"The best treatment for brain cancer is if the primary cancer can be removed without significant effect," said Dr. Jay Brooks, chairman of hematology/oncology at Ochsner Health System in Baton Rouge, La. "The standard treatment afterward is to be treated with a combination of chemotherapy and radiation for about six weeks followed by chemotherapy five days a month for about six months afterwards."
Temodar (Temozolomide) is the chemotherapy drug of choice these days. It's relatively new and has the advantage of being taken orally, Brooks said.
More recently, Yu and other researchers have been making headway with vaccines for this type of brain tumor. Yu and his co-authors just presented results of a phase II study on Monday at the American Society of Clinical Oncology (ASCO) annual meeting, in Chicago. "We've identified that a strong immune response is correlated with increased survival."
Other experts speculated that Sen. Kennedy may, in fact, already be enrolled in a vaccine trial currently under way at Duke University. "Having undergone surgery does make available other options, including this trial at Duke," Fisher said.
Results from the Duke trial, also presented at ASCO, reported median progression-free survival in patients receiving the vaccine (along with chemotherapy) of 16.6 months, whereas typically such patients might be expected to live only 6.4 months without a recurrence of the disease.
Still, cancer experts said Kennedy faces a difficult struggle.
Montefiore's Flamm said a patient with this type of brain tumor typically dies in about a year. "Some patients will die in less than a year, and others may live for two years," he said.
Dr. Ania Pollack, a neurosurgeon at the University of Kansas Hospital in Kansas City, agreed. "Life expectancy for a man Senator Kennedy's age with such a tumor is about 12 to 14 months," she said.
The U.S. National Library of Medicine has more on glioma.
SOURCES: Eugene S. Flamm, M.D., professor and chairman, department of neurosurgery, Montefiore Medical Center and Albert Einstein College of Medicine, New York City; Walter Jean, M.D., associate professor of neurosurgery, Georgetown University Hospital, Washington, D.C.; John S. Yu, M.D., director of surgical neuro-oncology, Cedars-Sinai Medical Center, Los Angeles; Paul Graham Fisher, M.D., associate professor of neurology and pediatrics and The Beirne Family Director of Neuro-Oncology at Packard Hospital, Stanford University, Stanford, Calif.; Jay Brooks, M.D., chairman of hematology/oncology, Ochsner Clinic Foundation, Baton Rouge, La.
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