1Division of Radiotherapy and Imaging, Cancer Research UK Cancer Imaging Centre, The Institute of Cancer Research, London, United Kingdom, 2The Royal Marsden Hospital, Sutton, United Kingdom, 3Department of Medicine, Centre for Pathology, Imperial College London, London, United Kingdom, 4Departments of Gynaecological Oncology and Radiology, Addenbrooke’s Hospital, Cambridge University Hospitals NHS Foundation Trust, Cambridge, United Kingdom