In his first interview since July, Sen. John McCain described his cancer as “vicious.”

Still, he says, he’s feeling confident. “I’m facing a challenge, but I’ve faced other challenges,” McCain told CNN.

McCain was diagnosed with an aggressive form of brain cancer – glioblastoma – in July. Doctors discovered a tumour while operating on a blood clot above McCain’s left eye. The blood clot and tumour were both removed.

Glioblastoma is the most common kind of high-grade brain tumour in adults. This strain of cancer is “high-grade” because it is likely to grow and spread quickly.

After surgery, McCain was treated with radiation and chemotherapy. He rested and recovered at home in Arizona while the Senate enjoyed a summer break.

But ever the politician, McCain made a point of returning to the Senate to cast a vote against the repeal of Obamacare. Fresh from surgery and initial treatment, McCain’s vote sent a very strong signal to the president and Republican party and was widely commented upon. 

McCain returns to the Senate this month, ready to continue leading the Senate Armed Services Committee.

He has, he claims, experienced no side effects other than “increased energy levels.”

“The prognosis is pretty good,” he explained. But still, McCain was reluctant to suggest that the long-term outcomes are “rosy.”

When asked how he wanted to be remembered, McCain said this: “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.”

For now, the 80-year-old senator and veteran will continue to balance his cancer treatments with the busy schedule of Senate duties.

“I am able to celebrate a wonderful life,” McCain reflected. “And I will be grateful for the additional time that I have.”