Savannah Guthrie, Valerie Harper

Despite being given only three months to live, Valerie Harper plans to enjoy each and every day she has left.

On Jan. 15, Harper, 73, was diagnosed with leptomeningeal carcinomatosis, a rare condition that occurs when cancer cells spread into the fluid-filled membrane surrounding the brain. Harper discussed her diagnosis on the Today show Tuesday, telling Savannah Guthrie that it really hit her when she heard her doctor say the cancer was "incurable."

Still, her outlook remains bright. "I'm not dying until I do," she says. "I promise I won't."

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Harper became famous when she landed the sidekick role of Rhoda Morgenstern on the CBS comedy The Mary Tyler Moore Show. She then starred in her own spin-off Rhoda. She won four Emmys and a Golden Globe for the role. In 2009, Harper was diagnosed with lung cancer, which she wrote about in her recent memoir I, Rhoda.

Check out her full Today interview below:

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