WASHINGTON (CBSNewYork/AP) — Longstanding Arizona Senator John McCain was diagnosed with brain cancer following the removal of a blood clot last week in Phoenix.

In a statement late Wednesday, doctors reveal that McCain has been diagnosed with glioblastoma, an aggressive cancer. GOP senators were meeting about the health care overhaul when they got the devastating news.

The Republican senator underwent a procedure to remove a blood clot from above his left eye last Friday.

“Subsequent tissue pathology revealed that a primary brain tumor known as glioblastoma was associated with the blood clot,” the statement continued.

McCain and his family are considering treatment options with the team at the Phoenix hospital, which may include a combination of chemotherapy and radiation according to the Mayo Clinic.

“It’s a primary brain tumor,” CBS News’ Chief Medical Correspondent Dr. Jon Lapook said. “It’s a very serious brain tumor. It’s the same one that killed Ted Kennedy.”

As CBS2’s Valerie Castro reported, there was speculation about the senator’s health after a congressional hearing when his questions for former FBI Director James Comey seemed jumbled and confused.

Dr. Lapook says it may have been a symptom of the tumor.

“The blood clot was in the front of the brain, the frontal lobe,” Dr. Lapook said. “That part of the brain controls communication, social interaction, language, so if he had an abnormality, if he had a clot, if he had what we know now is a cancer, then it’s understandable that might have affected his ability communicate.”

Stunned lawmakers reacted to the news from Capitol Hill.

“I’m thinking about a man that sacrificed more for his country than I can possible imagine and his family, and how we can help him beat this,” Senator John Kennedy (R-LA) said.

The senator’s daughter Meghan took to Twitter, saying: “The news of my father’s illness has affected every one of us in the McCain family.”

“It is an experience familiar to us, given my father’s previous battle with cancer — and it is familiar to the countless American families whose loved ones are also stricken with the tragedy of disease and the inevitability of age,” the statement continued.

Meghan added that “in all this, the one of us who is most confident and calm is my father.”

In a statement released Wednesday night President Trump said McCain “has always been a fighter.”

“Melania and I send our thoughts and prayers to Senator McCain, Cindy, and their entire family.”

Arizona’s senior senator and chairman of the Armed Services Committee had been recovering at his home. Doctors say his underlying health is excellent, according to the statement.

His absence had forced Majority Leader Mitch McConnell, (R-KY), to delay action on health care legislation.

In a statement, McConnell said: “John McCain is a hero to our Conference and a hero to our country. He has never shied from a fight and I know that he will face this challenge with the same extraordinary courage that has characterized his life. The entire Senate family’s prayers are with John, Cindy and his family, his staff, and the people of Arizona he represents so well.”

McCain was the GOP’s presidential nominee in 2008, when he and running mate Sarah Palin lost to Barack Obama.

Obama offered well wishes to his former opponent, tweeting: “John McCain is an American hero & one of the bravest fighters I’ve ever known. Cancer doesn’t know what it’s up against. Give it hell, John.”

McCain’s 2008 running mate released a statement on Facebook, saying: “John McCain is one tough fighter – we know he’ll face this diagnosis with courage and strength. Our family continues to lift John and his family up in prayer.”

McCain’s office said the senator “appreciates the outpouring of support he has received over the last few days.”

Further consultations with McCain’s care team at the hospital will indicate when he can return to the Senate, according to his office.

A Navy pilot, McCain was shot down over Vietnam and held as a prisoner for 5 ½ years.

(© Copyright 2017 CBS Broadcasting Inc. All Rights Reserved. The Associated Press contributed to this report.)