1 Martin Sjöström, PhD, Division of Oncology, Department of Clinical Sciences Lund, Lund University, Lund, Sweden; Anthony Fyles, MD; Fei-Fei Liu, MD; and David McCready, MD, Princess Margaret Cancer Centre and University of Toronto, Toronto, Ontario, Canada; Felix Y. Feng, MD, Department of Radiation Oncology, University of California San Francisco, San Francisco, CA; Corey W. Speers, MD, PhD and Lori J. Pierce, MD, Department of Radiation Oncology, University of Michigan, Ann Arbor, MI; Erik Holmberg, PhD, Department of Oncology, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden; Mårten Fernö, PhD, Division of Oncology, Department of Clinical Sciences Lund, Lund University, Lund, Sweden; Per Malmström, MD, PhD, Division of Oncology, Department of Clinical Sciences Lund, Lund University, Lund, Sweden, Department of Haematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden; and Per Karlsson, MD, PhD, Department of Oncology, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.