UNITED STATES - AUGUST 3: Sen. John McCain, R-Ariz., holds a news conference on the stimulus oversight report on Tuesday, ...

Senator John McCain says he’ll ‘be back soon, so stand-by’

Arizona Sen. John McCain says he’s grateful for the outpouring of support after his brain cancer diagnosis. He’s promising to be back soon.

In a tweet Thursday, McCain says: “I greatly appreciate the outpouring of support – unfortunately for my sparring partners in Congress, I’ll be back soon, so stand-by!”

READ MORE: Sen. John McCain has a brain tumor, doctors say

McCain’s office said late Wednesday that the 80-year-old senator had been diagnosed with cancer. Doctors in Arizona removed a blood clot above his left eye last Friday. Pathology tests revealed a brain tumor associated with the clot.

McCain has been recuperating at his home in Arizona.