Olivia Newton-John says she has been diagnosed with cancer for the third time in three decades.
The four-time Grammy-winner, who will turn 70 on Sept. 26, told Australian news program "Sunday Night" that doctors found a tumor in her lower back in 2017.
Newton-John says she's "treating it naturally and doing really well." The "Grease" star says for pain, she is taking cannabis oil, made from marijuana her husband grows in California. She has undergone radiation treatments and has cut sugar out of her diet.
She said, "I believe I will win over it."
She said she hopes her native Australia will legalize medical marijuana.
Newton-John was first diagnosed with breast cancer in 1992, undergoing a partial mastectomy and reconstruction. She was diagnosed with breast cancer again in 2013.
Throughout the 1970s and '80s, Newton-John had a string of hits, including "I Honestly Love You" and "Hopelessly Devoted to You" from the 1978 movie "Grease." Her most recent acting role was playing a scientist in the campy Syfy movie "Sharknado 5: Global Swarming" in 2017.