Singer Marianne Faithfull has been diagnosed with breast cancer.
Faithfull has postponed her forthcoming world tour
The 59-year-old singer has rescheduled a world tour, which was due to kick-off next month, until next year.
She became a household name in the 1960s, not least because of her relationship with Rolling Stones lead singer Mick Jagger.
"The disease has been quickly discovered by doctors in France," said her publicist. "The prognosis for a return to full health is excellent."
"I have absolute faith and confidence in my fantastic medical team and of course I will be well again, if not better than ever," said Faithfull in a statement.
"Next year's tour, I want to assure fans, will be one big celebration."
Publicist Rob Partridge said the cancer had been diagnosed at an early stage on Tuesday.
"Obviously she was very upset, but now she's in big fighting mood and determined to beat the cancer," he told BBC Radio Five Live.
Faithfull has been a recording artist for four decades, since being discovered by Rolling Stones' manager Andrew Loog Oldham.
Mick Jagger and Keith Richards wrote her first single, As Tears Go By, in 1964.
Faithfull's distinctive gravelly voice won her fans on both sides of the Atlantic, and she scored hits with songs such as Come and Stay With Me and This Little Bird.
She also pursued an acting career, appearing on stage in Chekhov's Three Sisters and taking the lead role in the film Girl On A Motorcycle
But the singer struggled with heroin addiction, which eventually led to a nervous breakdown.
She withdrew from the public eye for the majority of the 1970s, but she re-emerged with the punk-inspired album Broken English in 1979.
The ex-convent schoolgirl has since established herself as a sophisticated chanteuse, winning critical acclaim for her 1997 collection of Berlin ballads, 20th Century Blues.
An autobiography, Faithfull, was published in 1994, in which the singer recalled her failed romance with Jagger.
"The most that you can expect from a relationship that goes bad is to come out of it with a few good songs," she wrote.
Faithfull's most recent album was a greatest hits compilation, released in 2005.
She also plays a role in Sofia Coppola's upcoming biopic of Marie Antoinette.
Christine Fogg, chief exectutive of the Breast Cancer Care charity, said: "Kylie Minogue's experience of the disease has helped get the breast awareness message out to more people.
""We hope Marianne's experience helps reach even more," she added.