1. Department of Breast, Plastic and Reconstructive Surgery, Royal Hallamshire Hospital, Sheffield S10 2JF, UK
2. Department of Breast Screening and Breast Imaging, Royal Hallamshire Hospital, Sheffield S10 2JF, UK
3. Department of Histopathology, Royal Hallamshire Hospital, Sheffield S10 2JF, UK
4. Surgical and Interventional Trials Unit, Division of Surgery and Interventional Science, Faculty of Medical Sciences, University College London, London W1W 7JN, UK