Radiation for high-risk asymptomatic bone metastases – an implementation science perspective

External-beam radiation therapy (RT) is standard of care for pain relief in the treatment of bone metastases, but evidence is limited in the absence of symptoms. In a phase 2 randomized controlled trial, we evaluated the efficacy of radiation to asymptomatic bone metastases in preventing skeletal-related events (SRE) among adult patients with widely metastatic solid tumor malignancies. A total of 78 patients with 122 high-risk bone metastases were enrolled at three institutions across an affiliated cancer network in the United States between May 8, 2018, and August 9, 2021. Among 73 patients evaluable for the primary end point, SRE occurred 1.6% of bone metastases in the radiation arm compared to 29% of bone metastases in the standard of care arm at one year (P < .001). The proportion of patients experiencing fracture, cord compression, or surgical intervention (but not including radiation for pain alone) was 13.8% versus 0%, respectively. Radiation also reduced hospitalizations, reduced subsequent pain, and prolonged overall survival, but had no effect on quality of life. A confirmatory phase 3 randomized controlled trial with a pragmatic design has recently been approved through NRG and will be conducted in the NCI’s Community Oncology Research Program (NCORP), which will address important questions regarding generalizability and patient selection. In this presentation, we will review the pipeline for evidence-based practice, considerations for early clinical implementation, and opportunities for implementation research to ensure timely and equitable access to new interventions.