ESTRO 2024 - Abstract Book

S5528

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

ESTRO 2024

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1261

Mini-Oral

A safe clinical introduction of MR-only workflow in cone-beam CT based palliative spine radiotherapy

Dominique H Hofmeijer, Paul M Jeene, Roel GJ Kierkels

Radiotherapiegroep, Radiation oncology, Deventer, Netherlands

Purpose/Objective:

Spinal cord compression is an oncological emergency that requires immediate treatment. Palliative radiotherapy is often recommended following diagnostic MRI evaluation. In current practice, a simulation CT is used for treatment planning of the cone-beam CT (CBCT) guided palliative treatment. However, the simulation CT scan can cause delays, especially in satellite clinics with limited access to CT simulators at all locations. Although the diagnosis and treatment preparation process can be performed on MR-guided linear accelerators, the availability of these systems remains limited as well. We hypothesized that an MR-only workflow for CBCT based radiotherapy, using the diagnostic MRI and without the use of a simulation CT, is clinically feasible and results in non-inferior treatment delivery compared to conventional CT-based treatments.

Material/Methods:

We developed an MR-only workflow based on the available diagnostic MRI for palliative radiotherapy of patients with spinal cord compression treated with a dose of 1 x 8 Gy on vertebrae between Th1 and L5. The radiology department