As she currently managesstage 4 breast cancer,Olivia Newton-Johnhas shared that she secretly faced the disease in private back in 2013.

During lengthy sit-down on theAustralian television programSunday Night,theGreasestar 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 mostrecent 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.”

Billy Bennight/AdMedia

12th Annual Denim, Diamonds & Stars

Last year, Newton-John announced she’d been diagnosed withstage 4 breast cancerthat had metastasized to her back, but the 69-year-old actress has been treating the illness withnatural wellness therapies, includingmedicinal marijuana.

“I’m one of millions in this fight — I shouldn’t say fight — in thisjourney,” 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, atabloid reportalleged 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 theONJ Cancer Wellness & Research Centre’s Wellness Walk & Research Run,” read a statementposted 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 withJohn Travoltaat aGrease40th anniversaryevent,” 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

Jon Kopaloff/FilmMagic

BESTPIX - The Academy Presents “Grease” (1978) 40th Anniversary

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.

source: people.com