What to Know John McCain, the longtime Republican senator from Arizona, told Americans in July 2017 that he had glioblastoma

The McCain family said in a statement that he has discontinued medical treatment

The family said, "the progress of disease and the inexorable advance of age render their verdict"

Sen. John McCain, who revealed last year that he had been diagnosed with brain cancer, has decided to discontinue medical treatment, the McCain family said in a statement Friday.

The family said McCain has surpassed expectations for survival, but "the progress of disease and the inexorable advance of age render their verdict." The family added, "With his usual strength of will, he has now chosen to discontinue medical treatment."

McCain, in his sixth term representing Arizona, told Americans in July 2017 that he had glioblastoma, an aggressive form of brain cancer. The Republican underwent surgery that month to remove a blood clot in his brain.

McCain rebounded quickly, however, returning to Washington and entering the Senate in late July to a standing ovation from his colleagues. In a dramatic turn, he later cast a deciding vote against a Republican replacement for "Obamacare," the health care law approved under President Barack Obama. It earned him the wrath of President Donald Trump, who frequently cites McCain's vote at campaign events.

McCain's condition worsened last fall and he has been at his Arizona ranch since December, where he underwent physical therapy and received visitors.

The Vietnam War veteran, who would be 82 next week, has been away from the Capitol since December and has said he is not running for re-election.

The son and grandson of Navy admirals, McCain is a former Navy pilot and was held as a prisoner of war in Vietnam for more than five years. He was elected to Congress in the early 1980s and elected to the Senate in 1986, replacing Barry Goldwater who retired. McCain gained a reputation as a lawmaker who was willing to stick to his convictions rather than go along with party leaders. It is a streak that draws a mix of respect and ire.

McCain has also had melanoma, a deadly skin cancer, and is a long-term survivor. Doctors classified his brain cancer as a "primary tumor," meaning it's not related to his former malignancies.

Cindy McCain, John McCain's wife of nearly 40 years, shared the family statement on her personal Twitter account, writing, "I love my husband with all of my heart. God bless everyone who has cared for my husband along this journey." On Saturday, she followed up with a tweet saying the family was "overwhelmed by the outpouring of love and support from around the world."

The entire McCain family is overwhelmed by the outpouring of love and support from around the world. Thank you. — Cindy McCain (@cindymccain) August 25, 2018

McCain's 33-year-old daughter, "The View" co-host Meghan McCain, also tweeted the update on her father and added, "My family is deeply appreciative of all the love and generosity you have shown us during this past year. Thank you for all your continued support and prayers. We could not have made it this far without you - you've given us strength to carry on."

She has visited her father at his Arizona ranch, along with his friend former Vice President Joe Biden, whose son Beau Biden died in 2015 after being diagnosed with brain cancer. Other close friends, including Sen. Lindsey Graham of South Carolina and retired Connecticut Sen. Joe Lieberman, visited McCain at the Mayo Clinic in Phoenix.

"Becoming John McCain’s friend has been one of the great blessings of my life," Lieberman said in a statement. "Today I am praying for him and his family.”

I love my husband with all of my heart. God bless everyone who has cared for my husband along this journey. pic.twitter.com/v27sEbboii — Cindy McCain (@cindymccain) August 24, 2018

Members of Capitol Hill responded to the news Friday. Senate Majority Leader Mitch McConnell said he was "very sad" to hear about McCain, who he called a "dear friend."

"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," the Republican senator wrote on Twitter.

"My thoughts and prayers are with Senator McCain and his family," tweeted Senate Minority Leader Chuck Schumer, D-N.Y.

House Speaker Paul Ryan, R-Wis., said McCain "personifies service to our country." He wrote on Twitter that the members of the House are praying for the McCain family.

The GOP currently holds a bare 51-49 Senate majority.

McCain has been a frequent target of criticism from President Donald Trump, especially for his health care vote. Trump signed a military policy bill this month named for McCain, but in a sign of their testy relationship, the president made no mention of McCain's name in remarks at a signing ceremony.

Trump notably was not among those who tweet an outpouring of tributes for McCain in the hours after the health announcement.

At a fundraising dinner for the Ohio Republican Party Friday night, Trump failed to mention McCain, but gave shoutouts to Kanye West and Kim Kardashian.

Former Alaska governor Sarah Palin, who ran as McCain's vice presidential candidate in 2008, offered prayers for the McCain family "at this trying time.

"May comfort and peace envelope them. May my friend sense appreciation for his inspiration to serve something greater than self," she tweeted."

.@SenJohnMcCain is an American hero. Angela and I send our prayers to Senator McCain, Cindy and the entire McCain family. Read my statement: pic.twitter.com/oxzKPKXucq — Doug Ducey (@dougducey) August 24, 2018

The Associated Press contributed to this report.