Olivia Newton-John has shared that she secretly faced breast cancer in private back in 2013

As she currently manages stage 4 breast cancer, Olivia Newton-John has shared that she secretly faced the disease in private back in 2013.

During lengthy sit-down on the Australian television program Sunday Night, the Grease star discussed revelations from her upcoming memoir, including news that the cancer — which she had beaten over a decade earlier — had actually returned years before her most recent diagnosis in 2017.

She first discovered a lump on her right shoulder following a minor traffic accident in 2013. Though she initially believed it to be bruising sustained in the accident, further tests confirmed that it was a return of the cancer.

At the time, Newton-John made the choice to remain silent on the news. “I thought, ‘It’s my life,’ and I just decided to keep it to myself.”

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Olivia Newton-John
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Last year, Newton-John announced she’d been diagnosed with stage 4 breast cancer that had metastasized to her back, but the 69-year-old actress has been treating the illness with natural wellness therapies, including medicinal marijuana.

“I’m one of millions in this fight — I shouldn’t say fight — in this journey,” Newton-John said on Sunday’s show. “A lot of people see it as a fight, and wherever you choose to see it, that’s your prerogative. I see it as part of my mission.”

In August, a tabloid report alleged that Newton-John canceled a handful of speaking engagements due to the progression of the illness — a claim that she herself denied.

“Olivia Newton-John’s two upcoming speaking appearances in Australia were canceled due to scheduling conflicts with her upcoming promotional tour for her new book, Don’t Stop Believin’ and the ONJ Cancer Wellness & Research Centre’s Wellness Walk & Research Run,” read a statement posted on her social platforms. “Not illness as falsely reported.”

Quite the contrary: A source close to Newton-John tells PEOPLE that she’s been feeling fine and healthy as of late.

“She’s feeling and looking great and was just dancing with John Travolta at a Grease 40th anniversary event,” says the source. “Everything that’s being reported about her diagnosis is the same news she released last year.”

RELATED VIDEO: How Olivia Newton-John Is Staying Strong After Metastatic Breast Cancer Diagnosis

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Olivia Newton-John with her Grease costar John Travolta.
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And the famed “Physical” singer is not planning on slowing down any time soon. Along with the upcoming Australian release of her new memoir in September, the star is gearing up for her cancer walk just ahead of her 70th birthday on Sept. 26.

“She’s looking forward to walking with everyone at the Wellness Walk on September 16th in Melbourne,” the statement continued, “and is excited that this year the walk is going global and people can support it by becoming virtual walkers from wherever they are in the world.”