Sen. Kennedy Up and Walking After Brain Tumor Surgery

Whether Kennedy will be able to return to work in the Senate is not clear. "It's not just the physical part of it, it's a psychological burden. If Kennedy feels he wants to do it, he should do it," Flamm said. "I would think he'd have to wait until the end of radiation therapy. So, it would be several months."

The American Cancer Society estimates that 21,810 malignant tumors of the brain or spinal cord will be diagnosed this year in the United States. Approximately 13,070 people -- 7,420 men and 5,650 women -- will die from these malignant tumors. The cancers account for about 1.3 percent of all cancers and 2.2 percent of all cancer-related deaths in the United States.

The first evidence that a person has a malignant tumor is often a seizure like one Kennedy suffered last month, or stroke-like symptoms. Kennedy, the second-longest serving Democratic senator in Congress, suffered a seizure May 17 while at his family's Hyannisport, Mass., compound and was taken by helicopter to Boston.

In October 2007, a partially blocked carotid artery in Kennedy's neck was discovered during a routine magnetic resonance imaging (MRI) examination. Doctors cleared the blockage, and Kennedy was released to convalesce in Hyannisport.

Kennedy is the youngest of nine children, and became a U.S. senator in 1962. His older brother, President John F. Kennedy, was assassinated in 1963. Another brother, Robert Kennedy, who was also a U.S. senator, was assassinated in 1968 during his presidential campaign.

More information

The U.S. National Library of Medicine has more on glioma.