Working with PAHO/WHO to prioritize childhood cancer in the context of systems strengthening is central to St. Jude Children's Research Hospital (SJCRH)’s role as WHO Collaborating Centre for Childhood Cancer. This manuscript focuses on how SJCRH and PAHO/WHO have partnered to apply C5 (Country Collaboration for Childhood Cancer Control) to define and implement priority actions regionally, strengthening Ministry programs for childhood cancer, while implementing the Global Initiative for Childhood Cancer since 2018. Using C5, a tool developed by SJCRH, PAHO/WHO and SJCRH co-hosted regional/national workshops engaging authorities, clinicians and other stakeholders across 10 countries to map health systems needs and prioritize strategic activities (spanning Central America, Dominican Republic, Haiti, Brazil and Uruguay). SJCRH provided English/Spanish/Portuguese C5 versions/templates for analysis/prioritization exercises, and worked with PAHO/WHO and country teams to implement C5, analyze findings, and develop outputs. In an eight-country regional workshop, countries defined priorities within national/regional initiatives and ranked their value and political will, incorporating country-specific surveys and stakeholder dialogues. Each country prioritized one strategic activity for 2022-2023, exchanged insights via storytelling, and disseminated and applied results to inform country-specific and regional action plans. National workshops analyses have been incorporated into cancer control planning activities and collaborative work regionally. Implementation success factors include engaging actors beyond the clinic, enabling flexibility, and focusing on co-design with stakeholders. Joint implementation of C5 catalyzed prioritization and accelerated strategic activities to improve policies, capacity, and quality of care for children in the Americas, supporting Ministries to integrate childhood cancer interventions as part of systems strengthening.
