ESTRO 2025 - Abstract Book

S4103

RTT - Patient care, preparation, immobilisation and IGRT verification protocols

ESTRO 2025

Results: A total of 11 patients were enrolled in this study, the majority with vertebral metastases (n=10, 90.9%), all of whom received Three-Dimensional Conformal Radiation Therapy (3DCRT). The total pathway time was 2.6 ± 2.2 days. The average time required for patient positioning was 5:18 ± 0:42 minutes. The overall treatment time was less than 18 minutes in 90.9% of cases, with a mean dCT-CBCT matching time of 5:24 ± 1:36 minutes. Evaluation of the dCT-CBCT matching revealed mean rotational shifts of less than 2° across all three axes and mean translational shifts of less than 9 mm in each axes.

Figure 1. SIM-FREE Study’s Innovative Workflow for Palliative Patient RT

Table 1. Set-up shifts and treatment times for palliative patients in the SIM-FREE study

Conclusion: The SIM FREE pilot study demonstrates that planning the treatment of patients requiring palliative RT directly on a dCT, thereby eliminating the pCT step, does not compromise treatment reproducibility. This outcome is achieved through the use of SGRT for patient positioning, combined with a 6DoF couch to correct shifts before treatment delivery. In selected patients, this workflow streamlines the treatment pathway for palliative patients, increasing departmental efficiency and reducing patient burden.

Keywords: Palliative radiotherapy, Diagnostic CT planning

References: - Wong S, Roderick S, Kejda A, et al. Diagnostic Computed Tomography Enabled Planning for Palliative Radiation Therapy: Removing the Need for a Planning Computed Tomography Scan. Pract Radiat Oncol. 2021;11(2):e146-e153. doi:10.1016/j.prro.2020.10.010 - O'Neil M, Laba JM, Nguyen TK, et al. Diagnostic CT-Enabled Planning (DART): Results of a Randomized Trial in Palliative Radiation Therapy. Int J Radiat Oncol Biol Phys. 2024;120(1):69-76. doi:10.1016/j.ijrobp.2024.03.005