The Rolling Stones press office says the band's former bassist Bill Wyman has been diagnosed with prostate cancer, but is expected to make a full recovery.
A statement said Tuesday that 79-year-old Wyman is undergoing treatment for the disease, which was "caught in the early stages."
It said the Wyman family has asked for privacy.
Wyman joined the nascent Rolling Stones in 1962 and played with the group until 1993, making occasional guest appearances since then.
He now tours and records with his own blues-rock band, Bill Wyman's Rhythm Kings.
On Saturday Wyman attended the wedding of media mogul Rupert Murdoch and model-actress Jerry Hall — the former partner of Stones frontman Mick Jagger.