The left parietal lobe (one of four lobes in the brain's cerebral hemisphere) controls speech comprehension, and movement on the opposite side of the body.
Chicago, IL (PRWEB) May 20, 2008
Malignant gliomas are high-grade tumors that arise from the glial or "gluey" supportive cells in the brain. Approximately 42,000 primary brain tumors are diagnosed each year, of which 40 percent are malignant gliomas, making them the most commonly treated brain tumor in the United States, according to the American Brain Tumor Association (ABTA). Seventy-eight percent of all malignant tumors are gliomas.
U.S. Senator Edward Kennedy (D-Massachusetts) has been diagnosed with a malignant glioma in the left parietal lobe of the brain.
"The size of Senator Kennedy's tumor and the degree of infiltration of the tumor will be determining factors of symptoms, response to treatment, and ultimately, overall prognosis," said E. Antonio Chiocca, M.D., Ph.D., member of the ABTA Scientific Advisory Council, and professor and chairman of the Department of Neurological Surgery at The Ohio State University. "The left parietal lobe (one of four lobes in the brain's cerebral hemisphere) controls speech comprehension, and movement on the opposite side of the body."
There are different types of gliomas, however, Grade III or IV malignant gliomas. They are typically high-grade astrocytomas (arising from the star-shaped astrocytes cells which maintain the body's blood brain barrier, a filter designed to protect the brain from bacteria, viruses, and other potentially dangerous substances) or high-grade oligodendrogliomas (arising from oligodendrocytes, the fried-egg shaped cells that form a covering layer for nerve fibers in the brain).
A tumor develops when normal or abnormal cells multiply when they are not needed. A clump of these cells growing in the brain is called a brain tumor.
Benign vs. Malignant
The words "benign" or "malignant" generally refer to how unusual the tumor cells when compared to normal brain cells. A "benign" brain tumor consists of very slow growing cells, usually has distinct borders, and rarely spreads. When viewed microscopically, the cells have an almost normal appearance. Surgery alone might be an effective treatment for this type of tumor.
Malignant gliomas arise from normal brain tissue. They may invade and migrate away from the main tumor within the brain; however, malignant gliomas will rarely spread elsewhere in the body. A malignant brain tumor is life-threatening, invasive, and tends to grow at a more rapid pace than a benign tumor.
Currently, the most common treatment for a high-grade glioma is removal of as much tumor as possible, if surgically accessible, followed by radiation and chemotherapy, most often a drug called temozolomide (TEMODAR®). Another chemotherapy option is biodegradable polymer wafers, Gliadel, which are soaked in the chemotherapy drug carmustine (BCNU). The wafers are placed into the tumor cavity to deliver the chemotherapy directly to the migrating tumor cells without having to pass the blood brain barrier.
Researchers are exploring the biologic differences in gliomas as the basis for new treatment options. The treatments are tested in organized studies called clinical trials. Areas of research interest include angiogenesis inhibitors and differentiating agents, which may control the growth of new blood vessels surrounding the tumor. Monoclonal antibodies, such as the drug bevacizumab (Avastin®) may reduce blood supply to the tumor, thereby slowing or interrupting growth. In an area of medicine called immunotherapy, researchers are successfully collecting cells from tumor tissue for making vaccine or white cells from circulating blood, altering the cells, and then re-injecting them into the patient to trigger the body's immune system to fight against cancer cells.
For additional information about high-grade gliomas, please visit the ABTA web site at http://www.abta.org/index.cfm?contentid=230&Glioblastoma20Oligodendroglioma-%20Astrocytoma. Treatment information is available at http://www.abta.org/index.cfm?contentid=20&brain%20tumor-treatments-new%20treatments, and support resources for caregivers, families and friends, at http://www.abta.org/index.cfm?contentid=48.
Founded in 1973, the American Brain Tumor Association (ABTA) strives to eliminate brain tumors through research while meeting the support and education needs of brain tumor patients, their families and caretakers. The ABTA has awarded more than $12 million toward brain tumor research over the past 10 years, and offers 40+ publications, e-communications, a monthly newsletter, and social work resources, to help survivors and families to better understand a brain tumor diagnosis, and make educated treatment choices. Access ABTA services and information online at http://www.abta.org, send an e-mail to firstname.lastname@example.org, or call1- 800-886-2282.