Olivia Newton-John is ''confident'' her cancer battle will be a ''positive success story''.

The 'Grease!' actress recently revealed she has been diagnosed with metastatic breast cancer that's spread to her sacrum, 25 years after she first fought the disease, and has thanked fans for the support she has received around the world, while reassuring them that she believes her journey will be one of hope and inspiration.

She told People in a statement: ''I am really grateful for and touched by the worldwide outpouring of love and concern. Thank you. I am feeling good and enjoying total support from my family and friends, along with a team of wellness and medical practitioners both here in the US and at my Olivia Newton-John Cancer Wellness and Research Centre in Melbourne, Australia.

''I'm totally confident that my new journey will have a positive success story to inspire others! Love and light, Olivia.''

And the 'Physical' singer is already feeling better after undergoing a short course of photon radiation therapy and other natural treatments.

Her husband, John Easterling, said: ''[Her pain] has gone from [level] eight to about a two.''

John is as confident as his 68-year-old wife that she will beat the disease.

He said: ''We both have the same unshakable belief that she's going to have a wonderful success story.

''We're not trying to be positive. We have an absolute knowingness that we can turn this around.''

Olivia shared her diagnosis with close family and friends before going public last week, and they have been impressed by her positive attitude.

Friend and talk show host Leeza Gibbons said: ''She's not naive and doesn't get immobilised. She finds light in the darkest corners and just always has.''