1. Department of Radiation Oncology, University Medical Center Utrecht, Utrecht, The Netherlands
2. Department of Orthopedics, University Medical Center Utrecht, Utrecht, The Netherlands
3. Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht, The Netherlands
4. Division of Spine, Department of Orthopedics, University of British Columbia, Vancouver, British Columbia, Canada
5. Vancouver Spine Surgery Institute at Vancouver Coastal Health, Vancouver, British Columbia, Canada
6. Sunnybrook Odette Cancer Centre, University of Toronto, Ontario, Canada
7. Faculty of Medicine University of British Columbia, Vancouver, British Columbia, Canada
8. BC Cancer Agency, Vancouver Centre, Vancouver, British Columbia, Canada