Doctors say tests conducted after Kennedy suffered a seizure this weekend show a tumor in his left parietal lobe, the Associated Press reported. They say preliminary results from a biopsy of the brain identified the cause of the seizure as a malignant glioma.
Malignant gliomas are a common type of brain cancer diagnosed in about 9,000 Americans a year. Treatment of the condition depends on what specific tumor type is determined by further testing.
The 76-year-old senator has been hospitalized in Boston since Saturday, when he was airlifted from Cape Cod after a seizure at his home.
Kennedy's doctors said in a statement released to the AP that he has had no further seizures, is in good spirits and is resting comfortably.
His treatment will be decided after more tests but the usual course includes combinations of radiation and chemotherapy.
"He has had no further seizures, remains in good overall condition, and is up and walking around the hospital," said a joint statement issued by Dr. Lee Schwamm, vice chairman of the Department of Neurology at Massachusetts General Hospital and Dr. Larry Ronan, Kennedy's primary care physician.
According to the Mayo Clinic, some 17,000 Americans are diagnosed annually with primary brain tumors.
A spokeswoman for Kennedy's son, Rep. Patrick Kennedy, D-R.I., said the younger Kennedy was "comforted by the fact that his dad is such a fighter, and if anyone can get through something as challenging as this, it would be his father. ... He's hopeful that his father is going to beat this and be back at it. This is definitely a medical challenge that his dad can get through."
Known as "Teddy," Kennedy is the second-longest serving member of the Senate and remains a prominent figure in national Democratic Party politics. He was elected in 1962, filling out the presidential term won by his brother, John F. Kennedy.
Political colleagues expressed dismay over the seriousness of the diagnosis.
"I'm really sad," former Sen. Bob Kerrey, D-Neb., told the AP. "He's the one politician who brings tears to my eyes when he speaks."
Sen. Barack Obama, D-Ill., who recently won Kennedy's endorsement in his bid to win the Democratic presidential nomination, called the diagnosis "grim news."
"He has been fighting for over 40 years in the Senate on behalf of people in need and he'll fight hard to battle this illness," Obama said on MSNBC.
The words of concern stretched across the aisle to Kennedy's Republican colleagues in the Senate.
"I am so deeply saddened I have lost the words," Sen. John Warner, R-Va., said, according to news agencies. Both served on the Senate Armed Services Committee together.
Presumptive GOP presidential candidate Sen. John McCain, D-Ariz., called Kennedy the "last lion of the Senate."
Kennedy eldest brother, Joseph, was killed in a World War II airplane crash. President John Kennedy was assassinated in 1963 and his brother Robert, also a promising political figure, was assassinated in 1968.
