Newton-John, 69, first fought breast cancer in the 1990s. She beat the cancer, but discovered in 2013 a lump in her shoulder after a vehicle accident.
Other topics of the interview included Newton-John's favorite songs and her role in "Grease" - she initially didn't want the part of Sandy because she thought was too old.
The 69-year-old battled a second bout of cancer back in 2013 - a fight which she had made a decision to keep secret. I'd be lying if I said I never go there. "There are moments. I'm human, so if I allow myself to go there, I could easily create that big fear".
In a secret she kept "from nearly everyone", Olivia Newton-John was diagnosed with cancer in her shoulder five years ago-more than 20 years after she was first diagnosed with breast cancer, CNN notes.
"My dream is that in Australia soon, it will be available to all cancer patients.or any kind of disease that causes pain".
Newton-John said she's grateful to be living in California, where marijuana is legal.
In May 2017, Newton-John cancelled tour dates after her breast cancer returned and spread to her sacrum.
Thankfully, she's always had her husband, John Easterling by her side.
She has undergone radiation treatment and has cut sugar out of her diet. "That's all I've ever done since I was 15, so it's my life". There are people out there doing much worse than me.
"I feel so fortunate to have had the success I've had, and to do the wonderful things I do", she continued.
A rep for Newton-John did not immediately return a request for comment.