1 Canadian Association of Radiation Oncology, Markham, ON L3R 9X9, Canada; Department of Radiation Oncology and Developmental Radiotherapeutics, University of British Columbia, and BC Cancer Agency, Vancouver, BC V5Z 4E6, Canada. Electronic address: rhalperin@bccancer.bc.ca.
2 Department of Radiation Oncology and Developmental Radiotherapeutics, University of British Columbia, and BC Cancer Agency, Vancouver, BC V5Z 4E6, Canada.