Daily Star reports that in an excerpt taken from the book she wrote: "Before I put this book to bed, I wanted to share a little bit of positive news. "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. "She continued: "Right now, every little victory feels momentous. "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. "Sarah also revealed she was anxious about a Girls Aloud reunion with her bandmates due to her appearance as she underwent work to slow the cancer.