Sen. John McCain (R-Ariz.), 81, will discontinue medical treatment for brain cancer, his family said in a statement Friday.

The Vietnam War veteran, who survived five years as a prisoner of war and went on to become his party's presidential nominee in 2008, was diagnosed last July with a brain tumor following a procedure earlier in the year to remove a blood clot from above his left eye.

He has not voted since last December. In Friday's statement, his family revealed how the disease has worsened:

Last summer, Senator John McCain shared with Americans the news our family already knew: he had been diagnosed with an aggressive glioblastoma, and the prognosis was serious. In the year since, John has surpassed expectations for his survival. But the progress of disease and the inexorable advance of age render their verdict. With his usual strength of will, he has now chosen to discontinue medical treatment. Our family is immensely grateful for the support and kindness of all his caregivers over the last year, and for the continuing outpouring of concern and affection from John’s many friends and associates, and the many thousands of people who are keeping him in their prayers. God bless and thank you all.

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McCain has served in the U.S. Senate for more than three decades and ran for president twice. He lost the GOP nomination to George W. Bush in 2000 and was the Republican nominee in 2008 before losing to Barack Obama in the general election.

"Special Report" anchor Bret Baier on Friday said McCain is "an American hero" who not only served in country in the military but on Capitol Hill.

"If you think of any other figure in American history in political life who has spent his life serving the country, I don't think you can think of one who has served in as many ways as John McCain," Baier said.

Watch Baier's remarks above, and read more on McCain at

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