WASHINGTON, D.C. (CBSNewYork) – Sen. John McCain will no longer receive medical treatment for his brain cancer, his family said in a statement Friday.

The longtime Republican leader was diagnosed with a gioblastoma following the removal of a blood clot last summer.

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“In the year since, John has surpassed expectations for his survival. But the prognosis of the disease and the inexorable advance of age render their verdict,” his family said Friday. “With his usual strength of will, he has now chosen to discontinue medical treatment.”

MCain’s wife, Cindy, shared the statement on Twitter. “I love my husband with all of my heart. God bless everyone who has cared for my husband along this journey,” she wrote.

“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,” his daughter, Meghan, posted. “We could not have made it this far without you — you’ve given us strength to carry on.”

“Very sad to hear this morning’s update from the family of our dear friend @SenJohnMcCain,” Senate Majority Leader Mitch McConnell tweeted. “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.”

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“John McCain personifies service to our country. The whole House is keeping John and his family in our prayers during this time,” tweeted House Speaker Paul Ryan.

Days after his diagnosis, McCain returned to Congress, where he refused to vote for a Republican bill repealing the Affordable Care Act, also known as Obamacare.

“We could do better working together, Republicans and Democrats,” he said at the time.

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The 81-year-old war hero was first elected to the Senate in 1986 and is in his sixth term representing Arizona.

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“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,” the family’s statement continued. “God bless and thank you all.”