1. Department of Medical Physics, Grand River Regional Cancer Center, Kitchener, ON, Canada N2G 1G3
2. Department of Physics and Astronomy, University of Waterloo, Waterloo, ON, Canada N2L 3G1
3. Cancer Center of Southeastern Ontario, Kingston General Hospital, Kingston, ON, Canada K7L 5P9
4. Department of Oncology, Queens University, Kingston, ON, Canada K7L 5P9