Beyond the first course: Re-irradiation practices in Ontario — Insights from a provincial survey

Re-irradiation is an increasingly important aspect of cancer care, as more patients undergo more complex, multi-course radiation therapy, often across multiple cancer centres. To better understand how re-irradiation is planned and delivered, Ontario Health (Cancer Care Ontario)'s Radiation Treatment Program conducted a provincial review using administrative data and a structured survey of all 15 Regional Cancer Centres (RCC) that provide all radiation therapy to Ontario's 16 million people. The findings offered insight into current practices, including institutional policies, clinical workflows, technical planning methods, and interprofessional collaboration. As the complexity of care continues to grow, there is a clear need to harmonize these elements across institutions to support the safe, effective, and consistent delivery of re-irradiation. These findings are helping inform system-wide efforts to strengthen coordination and improve quality across the RCCs within Ontario.