KEY POINTS
- Study included a retrospective preclinical validation phase and a prospective clinical implementation phase of simulation-free, diagnostic computed tomography-based single-fraction radiotherapy for non-spine bone and soft tissue metastases.
- In the validation phase, 18 diagnostic computed tomography-based plans were generated and showed acceptable geometric and dosimetric agreement with cone-beam computed tomography-based reconstruction.
- In the implementation phase, 29 patients were treated across 37 sites between December 2023 and March 2025; prescribed single-fraction doses ranged from 6-20 Gy, with median dose 10 Gy.
- Treatment techniques included intensity modulated radiotherapy or volumetric modulated arc therapy in 76% of lesions; 11 lesions (30%) received single-fraction 12-20 Gy stereotactic radiotherapy.
- Mean delivered dose deviations were -1.4% for clinical target volume D99% and -3.4% for planning target volume D95%; no grade ≥3 acute toxicities were observed, and simulation was required in 2 cases.
CLINICAL TAKEAWAY
This study supports diagnostic computed tomography-based, simulation-free single-fraction radiotherapy as a feasible option for carefully selected non-spine palliative cases, including some high-dose stereotactic treatments. The workflow can reduce hospital visits and enable same-day treatment, but it requires careful patient selection because rotational setup error, positioning mismatch, pain, and longer on-couch time can compromise coverage. The evidence is encouraging but early: this was a small single-center implementation study without formal patient-reported outcomes or comparative clinical endpoints.