"It is looking better and better each test, but it's incurable," the actress, 74, told PEOPLE Monday night at the Fred and Adele Astaire Awards in New York. "I'm fine. People are wondering … Not fine, but it's not progressing."
The former Rhoda and Mary Tyler Moore Show star, who was a presenter at the event and beamed all evening, was radiant in a bright green top and matching earrings. She says she chooses to keep a positive outlook despite her diagnosis.
"I don't wake up saying, 'Oh, I'm going to die.' It's a waste of time. It really is," she said.
When Harper was first diagnosed, she was told she had three months to live; that was 18 months ago.
She goes for routine tests every eight weeks. "In my case I had a great response … my doctor doesn't use that term [remission]. He says, 'You try a therapy. There's a response or a nonresponse.' "
The actress, who turns 75 in August, has made no plans yet for the milestone birthday. "To be alive would be good," she said.