1. Department of Radiation Oncology, University Hospitals Seidman Cancer Center, Case Comprehensive Cancer Center, Cleveland, OH, USA.
2. Department of Radiation Oncology, Norris Cancer Center & Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
3. Department of Radiation Oncology, Henry Ford Hospital, Detroit, MI, USA
4. Department of Radiation Oncology, Odette Cancer Centre, University of Toronto, Toronto, ON, Canada
5. Department of Radiation Oncology, VU University Medical Center, Amsterdam, The Netherlands
6. Department of Radiation Oncology, The Methodist Hospital & Weill Cornell Medical College, Houston, TX, USA
7. Department of Radiation Oncology, Princess Margaret Cancer Centre, University of Toronto, Toronto, ON, Canada