Kennedy's Brain Tumor 'Very Bad News'

May 21, 2008 — -- Many of us may not have heard the term "malignant glioma" before today. In short, it's a cancerous brain tumor -- and the diagnosis now facing Sen. Edward Kennedy, D-Mass.

"This is very bad news," said Dr. John A. Wilson, associate professor of neurosurgery at Wake Forest University School of Medicine in Winston-Salem, N.C.

The word glioma comes from "glia," the gluelike cells that hold the brain together, said Dr. Lynne Taylor, a fellow with the American Academy of Neurology. A glioma is a primary brain tumor, one that begins in the brain without spreading from another location in the body. The word "malignant" indicates that it's both cancerous and rapidly growing.

Malignant gliomas make up more than half of the 18,000 primary malignant brain tumors diagnosed in the United States each year, according to the National Cancer Institute. The tumors are graded from I to IV according to severity, with Grade IV being the most aggressive tumor. The NCI estimates that the median survival for Grade III tumors is three to five years, and less than a year for Grade IV.

Because of the 76-year-old senator's age and the fact that the tumor is labeled as malignant, it's likely a Grade III or IV tumor, according to Dr. Nina Paleologos, chair of the section of neuro-oncology for the American Academy of Neurology.

To identify the tumor's type, surgeons at Massachusetts General Hospital performed a brain biopsy, in which surgeons remove a small amount of tissue from the brain. If the tumor can be removed without injury to the brain, it is often removed completely, said Dr. Clifford B. Saper, chairman of the department of neurology at Beth Israel Deaconess Medical Center in Boston.

In Kennedy's case, they didn't remove it. There could be two reasons for that decision: Either doctors wanted to figure out the type of tumor before they rushed to surgery, or the tumor was too difficult to remove, according to Paleologos.

"Without seeing his pictures, it's too hard to say," she said.