The US Senator has been diagnosed with a brain tumour
US Senator John McCain has been diagnosed with a brain tumour, his office has said.
The Arizona politician had a blood clot removed from above his left eye last Friday and tissue analysis since the procedure revealed a brain tumour, known as glioblastoma, was associated with the clot.
His doctors in Phoenix said the 80-year-old is reviewing treatment options that may include a combination of chemotherapy and radiation.
They added he is recovering from his surgery "amazingly well" at home and that his underlying health is "excellent."
In a statement, Mr McCain's office said the senator "appreciates the outpouring of support he has received over the last few days."
"He is in good spirits as he continues to recover at home with his family in Arizona.
"He is grateful to the doctors and staff at Mayo Clinic for their outstanding care and he is confident that any future treatment will be effective."
This is not the senator's first experience of cancer - he had several malignant melanomas removed from his skin in the 1990s and 2000s, including an invasive melanoma in 2000.
Glioblastomas are particularly aggressive and the American Cancer Society puts the five-year survival rate for patients over 55 at about 4%.
But Mr McCain's daughter Meghan described him as "the toughest person I know".
"It won't surprise you to learn that in all this, the one of us who is most confident and calm is my father.
"Cancer may afflict him in many ways but it will not make him surrender. Nothing ever has."
Mr McCain has been a Republican senator for six terms and was also a presidential nominee in 2008, losing to Barack Obama.
During the campaign in October that year, Mr McCain was approached by a voter who expressed fear that Mr Obama was "an Arab."
Instead of taking the opportunity to speak badly of his rival, he corrected the lady and replied: "He's a decent family man and citizen who I just happen to have disagreements with on fundamental issues and that's what this campaign is all about."
On hearing of Mr McCain's medical condition, Mr Obama tweeted: "John McCain is an American hero and one of the bravest fighters I've ever known. Cancer doesn't know what it's up against - give it hell, John."
As a Navy pilot, Mr McCain was shot down over Vietnam during the war there and was held as prisoner for five years.
US President Donald Trump said that the senator "has always been a fighter".
He added: "Melania and I send our thoughts and prayers to Senator McCain, Cindy and their entire family. Get well soon."
Mr Trump was criticised for denigrating Mr McCain's military record during the 2016 election campaign after he said he was "not a war hero", adding: "I like people who weren't captured".
Senate Majority Leader Mitch McConnell described Mr McCain as "a hero to our Conference and a hero to our country".
Mr McConnell added: "He has never shied from a fight and I know that he will face this challenge with the same extraordinary courage that has characterised his life."