Valerie Harper is determined to enjoy her last days no matter what. In her first TV interview about her recent terminal brain cancer diagnosis, the 73-year-old Emmy-winning actress opens up to the TODAY show's Savannah Guthrie that she remains optimistic.

Diagnosed with leptomeningeal carcinomatosis -- in which cancer cells metastasize into the fluid-filled membrane enveloping the brain -- the Mary Tyler Moore star has reportedly been given three to six months to live. But Harper told Guthrie, "'Incurable' is a tough word . . . I'm not dying until I do. I promise I won't."

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Harper, who played Rhoda Morganstern on The Mary Tyler Moore Show and its spinoff, Rhoda, explained she's "more than hopeful . . . I have an intention to live each moment fully."

Still, the beloved Valerie star clarified she's not in denial about the reality of her situation. "I don't mean this to be Pollyanna—I allow myself the grief."

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"I also feel so much better not hiding," she says of coming clean with the public. "It feels awful damn good to be open about it, face it and see what you can do. If you die, you're not a failure. You're just somebody who had cancer. And that's the outcome."

This article originally appeared on Valerie Harper on Terminal Cancer Diagnosis: "I'm Not Dying Until I Do"