1. Department of Radiation Oncology, CancerCare Manitoba, Winnipeg, MB, Canada
2. Department of Radiology, University of Manitoba, Winnipeg, MB, Canada
3. Department of Epidemiology and Cancer Registry, CancerCare Manitoba, Winnipeg, MB, Canada
4. Department of Radiology, University of Calgary, Calgary, AB, Canada
5. Department of Radiation Oncology, Tom Baker Cancer Center, Calgary, AB, Canada
6. Research Institute in Oncology and Hematology, CancerCare Manitoba, Winnipeg, MB, Canada