Sen. John McCain passes away at 81

Senator John McCain passed away at 81 years old on Saturday afternoon, according to a statement from McCain's office.

McCain died at 4:28 p.m. Saturday afternoon, with his wife Cindy and his family by his side.

"At his death, he had served the United States of America faithfully for sixty years," the statement read.

McCain's death comes just a day after medical treatment had been discontinued, after he was diagnosed with having brain cancer.

"John has surpassed expectations for his survival," the McCain family said in a statement on Friday when the announcement was made. "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."

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McCain spent five years as a prisoner of war when his plane was shot down in 1967 during a bombing mission over North Vietnam.

He entered politics in 1982 when he was elected to the House of Representatives. He became Senator in 1986 and became a stalwart of conservatism.

He was unsuccessful when he sought the Republican nomination for president in 2000. He got the nomination in 2008, however, lost to Barack Obama.

>>Washington Insider Jamie Dupree: In the halls of Congress, McCain cut a unique political path

McCain has battled various cancers for many years.

Doctors discovered John McCain's brain tumor after he underwent surgery in July 2017 to remove a blood clot from above his eye. He was previously diagnosed with melanoma in 1993, 2000 and 2002, and underwent treatment each time. Those cancers did not spread, according to John McCain's doctors.

Glioblastoma is a particularly aggressive form of cancer and the prognosis is often poor, according to the American Brain Tumor Association. The average survival rate for patients with malignant glioblastoma is around 14 months if the person gets treatment. Around 10 percent of patients with the disease live for five years or longer.

Family, friends and politicians on both sides of the aisle shared their condolences.

My deepest sympathies and respect go out to the family of Senator John McCain. Our hearts and prayers are with you!

In the halls of Congress, Sen John McCain R-AZ cut a unique political path that earned him the scorn of both parties <a href="https://t.co/ts8qH5SCBM">https://t.co/ts8qH5SCBM</a> <a href="https://t.co/1OvOvGUQbe">pic.twitter.com/1OvOvGUQbe</a>

John McCain was many things – a proud graduate of the Naval Academy, a Senate colleague, a political opponent.<br/> <br/> But, to me, more than anything, John was a friend. He will be missed dearly. <a href="https://t.co/AS8YsMLw3d">pic.twitter.com/AS8YsMLw3d</a>

John McCain was a giant of our time—not just for the things he achieved, but for who he was and what he fought for all his life. He will always be listed among freedom's most gallant and faithful servants.

John McCain was my friend. I will remember the good times. My family and I send prayers for Cindy and the McCain family.<br/> - Sarah Palin and family <a href="https://t.co/KRvcIQ99cA">pic.twitter.com/KRvcIQ99cA</a>

Cox Media Group