Sarah Harding has told how she celebrated a "victory" in December when her cancer treatment caused the tumours in her brain and lung to shrink.
She has now written her autobiography, Hear Me Out, and in an excerpt obtained by the Daily Star revealed she had “a little bit of positive news” in December.
"Before I put this book to bed, I wanted to share a little bit of positive news,” Harding says. "MRI scans at the end of December revealed that the tumours in my brain and in my lung have shrunk a bit with the treatment."
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The singer, 39, said that although she wasn’t sure what it meant, at least it was moving in the right direction.
“Right now, every little victory feels momentous,” she said. "With this news under my belt, I was able to enjoy a relaxing quiet Christmas with mum and yes, I got plenty of lovely Christmas pressies."
Hear Me Out is due to be released this week.
The singer has previously said penning a book about her life was giving her something positive to focus on.
She has also explained that she named it after the song she wrote on the second Girls Aloud album What Will the Neighbours Say? as the lyrics "have always meant a lot" to her.
Girls Aloud rose to fame after winning TV show Popstars: The Rivals in 2002 and are known for songs such as Sound Of The Underground, Something Kinda Ooooh and The Promise.
They went on hiatus in 2009 and eventually went their separate ways.
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