"I'm facing a challenge, but I've faced other challenges," McCain said. "And I'm very confident about getting through this one as well."
The Arizona Republican, who was diagnosed with brain cancer in July, said he will receive a magnetic resonance imaging test on Monday and expressed optimism about his condition.
"I'm fine," McCain told anchor Jake Tapper. "The prognosis is pretty good. Look, this is a very vicious form of cancer that I'm facing, but all the results so far are excellent."
McCain returned to Washington as the Senate came back from its August recess last week, and he said he planned to focus in the coming week on a key defense bill.
In the interview,
the former Republican presidential candidate praised his health care providers at length and said new medical technologies were part of his hopeful disposition.
"I'm getting the best treatment that anybody could get," McCain said.
Still, he stressed the seriousness of the disease and said he did not want to paint a "rosy picture" for what he said is a tough form of cancer.
The longtime senator and storied prisoner of war also said he was grateful to be able to celebrate his life and draw upon memories, including his underdog bid in 2000 for the Republican presidential nomination. He even noted with some humor that although he is now regarded as a statesman and elder leader of his party, he once stood near the bottom of his class at the Naval Academy.
Although McCain said he hoped to beat the disease and live as long as possible, he seemed to be at peace.
"Every life has to end one way or another," McCain said.
Asked how he wanted to be remembered, McCain responded: "He served his country, and not always right -- made a lot of mistakes, made a lot of errors -- but served his country, and I hope we could add, honorably."