Singer Marianne Faithfull has breast cancer, her publicist said Thursday.
The singer and actress, who appears in Sofia Coppola’s upcoming film Marie Antoinette, discovered a lump in one of her breasts while staying with friends in Paris, her rep, Rob Partridge, tells PEOPLE. The disease was diagnosed on Tuesday.
Faithfull, 59, has postponed her world tour, which was due to kick off next month.
“Obviously she was upset on hearing the news,” Partridge tells PEOPLE. “But she is now in a fighting mood. She is coming out fighting.”
Faithfull, who lives in Ireland, said in a statement, “I have absolute faith and confidence in my fantastic medical team and of course I will be well again, if not better than ever. Next year’s tour, I want to assure fans, will be one big celebration.”
“The disease has been quickly discovered by doctors in France,” Partridge said in a statement. “The prognosis for a return to full health is excellent. Indeed, Marianne Faithfull is looking forward to playing the re-scheduled tour in 2007.”
Faithfull began her music career in 1964 at age 17 and had a hit that year with the Mick Jagger-Keith Richards-penned “As Tears Go By,” which the Rolling Stones recorded a year later.
In her 1994 book Faithfull: An Autobiography, which chronicled her career, drug addictions and tumultuous four-year affair with Jagger.
She’d begun dating Jagger when she was just 19 and briefly abandoned her singing career because “it wasn’t as important as being with Mick,” she told PEOPLE in 1994. But as she spiraled into drug addiction, they split in the late ’60s. ”Ours was just a classic parting of ways,” she said. ”He went in one direction – up – and I went down.”
Faithfull cleaned up, launched an acting career (among other roles, she played God on the British sitcom Absolutely Fabulous) and returned to music, in 1979 releasing the critically acclaimed album Broken English. Her most recent studio album was 2005’s Before the Poison.
Partridge tells PEOPLE, “Marianne will be on the road for rest of her life.”