Tests performed over the weekend at Massachusetts General Hospital in Boston indicated that Senator Edward M. Kennedy, 76, has a type of cancer known as a malignant glioma in the left parietal lobe, the upper left portion of his brain.

His treatment for the malignant glioma will be decided after more tests but the usual course includes combinations of radiation and chemotherapy. Kennedy has been hospitalized in Boston since Saturday, when he was airlifted from Cape Cod after a seizure at his home.

“He has had no further seizures, remains in good overall condition, and is up and walking around the hospital,” said the statement by Dr. Lee Schwamm, vice chairman of the Department of Neurology at Massachusetts General Hospital and Dr. Larry Ronan, Kennedy’s primary care physician.

They said Kennedy will remain in the hospital “for the next couple of days according to routine protocol.”

Kennedy’s wife and children have been with him each day since he was hospitalized. His son, Patrick Kennedy, a Democratic representative from Rhode Island, plans to stay at the hospital for the time being.

“Obviously it’s tough news for any son to hear,” said spokeswoman Robin Costello. “He’s 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. So he’s optimistic, he’s hopeful, but obviously he’s concerned.”

President Bush was notified by his staff of Kennedy’s diagnosis at 1:20 p.m.

“He said he was deeply saddened and would keep Senator Kennedy in his prayers,” spokeswoman Dana Perino said.

Malignant gliomas are a type of brain cancer diagnosed in about 9,000 Americans a year — and the most common type among adults. It’s an initial diagnosis: How well patients fare depends on what specific tumor type is determined by further testing.

Average survival can range from less than a year for very advanced and aggressive types — such as glioblastomas — or to about five years for different types that are slower growing.

News of the diagnosis hit hard for his Democratic colleagues, as well as his Republican ones.

Kennedy, the second-longest serving member of the Senate and a dominant figure in national Democratic Party politics, was elected in 1962, filling out the term won by his brother, John F. Kennedy.

He comes from one of the most famous political families. His eldest brother, Joseph, was killed in a World War II airplane crash. President Kennedy was assassinated in 1963 and his brother Robert was assassinated in 1968.

Kennedy is active for his age, maintaining an aggressive schedule on Capitol Hill and across Massachusetts. He has made several campaign appearances for Senator Barack Obama in February, and most recently last month.

This news came as a surprise to the Kennedy family as well as the rest of the country.  I know that everyone wishes him a fast and successful recovery!