In this Oct. 25, 2017 file photo, Senate Armed Services Chairman John McCain, R-Ariz., pauses before speaking to reporters during a meeting of the National Defense Authorization Act conferees, on Capitol Hill in Washington. Credit: J. Scott Applewhite | AP

Sen. John McCain is discontinuing medical treatment, his family announced Friday, just more than a year after the maverick Republican from Arizona was diagnosed with brain cancer.

Their statement said McCain, who turns 82 this week, had surpassed expectations for his survival since his diagnoses last July of glioblastoma, a terminal form of brain cancer.

“But the progress of disease and the inexorable advance of age render their verdict” and the senator has decided to end medical treatment, the statement said.

McCain, a celebrated Navy pilot in the Vietnam War, has been absent from Washington since last December. While undergoing treatment in Arizona, he has kept a low profile, issuing written statements on major news developments but offering the public few glimpses of his condition.

“I love my husband with all of my heart,” Cindy McCain wrote on Twitter Friday shortly after the family statement was released. “God bless everyone who has cared for my husband along this journey.”

During a long and sometimes polarizing political career, McCain has served in the Senate for more than three decades and twice sought the presidency.

Friday’s news prompted an immediate outpouring of support on social media and elsewhere from McCain’s colleagues in Congress.

“Very sad to hear this morning’s update from the family of our dear friend @SenJohnMcCain,” Senate Majority Leader Mitch McConnell, R-Kentucky, said on Twitter. “We are so fortunate to call him our friend and colleague. John, Cindy, and the entire McCain family are in our prayers at this incredibly difficult hour.”

“John McCain personifies service to our country,” House Speaker Paul D. Ryan, R-Wisconsin, said in a tweet. “The whole House is keeping John and his family in our prayers during this time.

McCain first arrived on the national stage as a prisoner of war in Vietnam after his plane was shot down over Hanoi in 1967.

In 1982, he was elected to the U.S. House of Representatives. Four years later, he won his seat in the Senate, where he established himself as a leading voice on national security and foreign policy.

McCain has also cultivated a reputation as an independent willing to work with Democrats on issues such as immigration and campaign financing.

In recent years, he has clashed sharply with President Donald Trump, who said early in the 2016 presidential campaign that McCain was not a war hero.

Following his diagnosis and initial treatment, McCain returned to the Senate and cast a pivotal vote against a Republican bill to undo the Affordable Care Act. During a post-midnight roll call on the Senate floor, he turned his thumb down and effectively thwarted one of the GOP’s signature promises of recent years.

Trump has continued to castigate McCain for the vote.

McCain collaborated with a longtime adviser, Mark Salter, on a memoir, “The Restless Wave,” that was released in May.

Among other things, the book captured McCain’s difficult relationship with Trump. The president, he wrote, “has declined to distinguish the actions of our government from the crimes of despotic ones.”