“There’s no easy way to say this and actually it doesn’t even feel real writing this, but here goes,” the 38-year-old posted to her Twitter and Instagram accounts.
“Earlier this year I was diagnosed with breast cancer and a couple of weeks ago I received the devastating news that the cancer has advanced to other parts of my body,” Harding began.
“I’m currently undergoing weekly chemotherapy sessions and I am fighting as hard as I possibly can.”
“I understand this might be shocking to read on social media and that really isn’t my intention. But last week it was mentioned online that I had been seen in hospital, so I feel now is the time to let people know what’s going on and this is the best way I can think of to do so,” she said of her decision to announce the news to fans.
“My amazing mum, family and close friends are helping me through this, and I want to say a thank you to the wonderful NHS doctors and nurses who have been and continue to be heroes.”
“I am doing my very best to keep positive and will keep you updated here with how I’m getting on. In the meantime I hope you’ll all understand and respect my request for privacy during this difficult time,” she concluded.
Following the announcement, Harding’s Girls Aloud bandmates rallied around her for support.
Cheryl Tweedy responded to her friend’s news by posting a broken heart emoji on Twitter, while Nicola Roberts wrote: “It goes without saying that this is blindsiding. Sarah, you’re so loved and supported.”
Nadine Coyle shared the girls’ sentiments, writing: “I love you!!!! You have always been able to achieve miracles when needed! I am here for the all the way & always will be!!!”
Girls Aloud formed in 2002 as part of UK reality series Popstars: The Rivals and went on to find massive success in their native UK.