Olivia Newton-John postpones tour as she reveals she has breast cancer

Olivia Newton-John has breast cancer.

The 68-year-old star took to Facebook on Tuesday to reveal she was "reluctantly" postponing her upcoming tour dates because of the diagnosis.

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"Olivia Newton-John is reluctantly postponing her June U.S. and Canadian concert tour dates," the post read. "The back pain that initially caused her to postpone the first half of her concert tour, has turned out to be breast cancer that has metastasized to the sacrum."

Newton-John will undergo photon radiation therapy in addition to "natural wellness therapies" to combat the cancer. The post went on to say that she's "confident she will be back later in the year, better than ever, to celebrate her shows."

See photos of Olivia Newton-John:

The diagnosis comes 25 years after the former "Grease" star was diagnosed with breast cancer back in 1992. As E! News notes, she underwent a partial mastectomy, chemotherapy and breast reconstruction for her treatment back then.

"I decided on my direction of therapies after consultation with my doctors and natural therapists and the medical team at my Olivia Newton-John Cancer Wellness and Research Centre in Melbourne, Australia," Tuesday's statement continued, before noting that she wants to "focus on her treatment and healing."

The Olivia Newton-John Cancer Wellness and Research Centre was built back in 2008.

Read Olivia Newton-John's full Facebook post below:

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