TV star Valerie Harper says she is doing well in her fight against a rare form of brain cancer and that her medical team is encouraged by her recent test results.

"I am not absolutely cancer-free. I wish I were," the 74-year-old actress said in a statement. "Right now what I am is cautiously optimistic about my present condition and I have hope for the future."

Harper, best known for roles in "The Mary Tyler Moore Show" and "Rhoda," has leptomeningeal carcinomatosis, a rare condition that occurs when cancer cells spread into the fluid-filled membrane surrounding the brain.

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In March of last year, doctors told her she may only have months to live. The cancer was deemed inoperable and she underwent chemotherapy.

A few weeks ago her doctors were pleasantly surprised at her test results, she says.

"(The oncologist) looked at the scans and said, 'Oh my God, Valerie, this is very encouraging!'" she said. "I'm now the poster child for not believing everything I'm told."

In an interview with "Closer" magazine, the star, who is appearing in the Hallmark Channel's new series, "Signed, Sealed, Delivered," says that she is on what is called a "pulse dose" of medication. This means she takes large doses of pills all at once, once a week. "They can be difficult, but I try to sleep them off," she told the magazine.

She has to see her doctor only once every eight weeks.

"There may come a time when I'm not feeling good," Harper said. "But then again, that time never come!"

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