1 Department of Oncology, London Health Sciences Centre, London, Ontario, Canada.
2 Centre Hospitalier de l'Université de Montréal, Montréal, Quebec, Canada.
3 Radiation Medicine Program, Princess Margaret Cancer Centre, Toronto, Ontario, Canada; Department of Radiation Oncology, University of Toronto, Toronto, Ontario, Canada.
4 Northeast Cancer Centre, Sudbury, Ontario, Canada.
5 Grand River Cancer Centre, Kitchener, Ontario, Canada.
6 Alfred Health, Melbourne, Australia.
7 Department of Oncology, London Health Sciences Centre, London, Ontario, Canada. Electronic address: [email protected].