June 4, 2008 > Why Brain Cancers like Senator Ted Kennedy's Are Difficult to Treat
Why Brain Cancers like Senator Ted Kennedy's Are Difficult to Treat
Washington Hospital Neurosurgeon Shares Insight on New Therapies and Treatments for Patients with Brain Tumors
On May 20, America learned that one of its elder statesmen, Sen. Edward Kennedy, has been diagnosed with a brain tumor. Regardless of party affiliation, politicians and other citizens from around the country were saddened and wished Kennedy and his family well.
The news is even more unfortunate because the 76-year-old senator's tumor is a glioblastoma multiforme or GBM, the most aggressive of all primary brain tumors. Primary brain tumors originate in the brain rather than spreading, or metastasizing, from a tumor located in another part of the body.
"The average length of survival for people with GBM is 12 to 14 months, and life expectancy is often shorter for patients over 60 or 65," says neurosurgeon Sandeep Kunwar, M.D., co-director of Washington Hospital's Gamma Knife Program, which performs radiosurgery on some patients with GBM. Gamma Knife radiosurgery is a revolutionary, less invasive alternative to traditional open-brain surgery and daily radiation treatment for patients with brain tumors.
GBM is the most common primary brain tumor, striking 10,000 to 12,000 Americans of all ages each year. Nevertheless, the tumor is relatively rare compared with brain tumors that have metastasized from elsewhere in the body. About 200,000 Americans are diagnosed with metastatic brain tumors annually.
"Unfortunately, GBM results in a very high functional loss of life because it can strike a person at the prime of life, when he or she is most productive," explains Dr. Kunwar. "With some cancers, people continue to lead active, productive lives as they receive treatment. Hopefully, they will experience a remission or cure. With GBM, this is not the case."
Common symptoms of GBM are seizures, nausea and vomiting, headaches that become progressively worse, a declining ability to move certain parts of the body, and weakness or numbness in the face or arm. Treatment usually involves surgery to remove as much of the tumor as possible. Radiation therapy and chemotherapy can also be used to help control growth of the tumor and prolong the patient's life.
On average, each of these measures can add two to three months to a patient's life. All are consider "palliative," because they cannot cure the disease but can help the patient to live longer and more comfortably.
"GBM is like a weed because it can intertwine with cells in any part of the brain," explains Dr. Kunwar. "If the affected brain tissue isn't functional, it's possible to remove the tumor. However, if the affected cells are involved with function, the tumor can't be removed without resulting in major neurological deficits. In that case, the tumor, or parts of it, must be left in place. In the case of Senator Kennedy, the tumor is located on the left hand, dominant side of the brain, which affects memory, speech and other critical neurological functions."
At Washington Hospital, highly trained physicians sometimes use the advanced Gamma Knife to remove parts of a GBM tumor. Treatment is usually combined with chemotherapy in a limited role. This regimen can be effective if the tumor has one focal area that is especially active.
Major research efforts are currently being conducted around the world to identify other effective treatments for GBM. Clinical trials are being done on numerous drugs, including Avastin. Researchers are also studying vaccines, gene therapy and novel drug delivery techniques.
Effective treatment for more common tumors
The facts about GBM are grim. However, there's better news for people who suffer from the more common metastatic brain tumor.
"Gamma Knife radiosurgery can be used to treat these types of brain tumors very effectively with a control rate of more than 90 percent," states Dr. Kunwar. "In the past, whole-brain therapy, including radiation therapy and chemotherapy, have been the standard of care for metastatic brain tumors. However, the less invasive Gamma Knife has altered this standard while improving long-term control of the tumor."
In contrast with traditional treatment for brain cancer, patients undergoing Gamma Knife surgery experience almost no pain and are able to return home the same day or after staying in the hospital overnight. With whole-brain therapy, the brain's healthy tissue is also affected, resulting in side affects such as memory loss, brain shrinkage, hair loss and fatigue. The Gamma Knife procedure focuses on the precise area of the tumor, leaving nearby healthy tissue untouched.
For more information about glioblastoma multiforme, visit the website of the American Cancer Society at www.cancer.org. To learn more about the Taylor McAdam Bell Neuroscience Institute and the Gamma Knife Program at Washington Hospital, call (510) 745-6480 or visit www.whhs.com, click on "Services & Programs" and select "Taylor McAdam Bell Neuroscience Institute" from the drop-down menu.