D Dearnaley1, I Syndikus2, S Gulliford3, E Hall3. 1. The Institute of Cancer Research, London, UK; Royal Marsden NHS Foundation Trust, London, UK. Electronic address: david.dearnaley@icr.ac.uk. 2. Clatterbridge Centre for Oncology, Bebington, UK. 3. The Institute of Cancer Research, London, UK.