Room: Exhibit Hall | Forum 6
Purpose: To take full advantage of all the benefits in an MRI-only workflow, it is important to implement the technique in such a way that no new uncertainties or unnecessary tasks are introduced. This study aimed to safely implement MRI-only radiotherapy for prostate cancer patients and document potential pitfalls of the workflow.
Methods: The MRI-only Prostate RadiOTherapy Excluding CT (MR-PROTECT) study is a prospective feasibility trial studying the MRI-only workflow. Twenty-eight patients have been included in the study. An adapted workflow with integrated QA was created. An MRI-simulation (GE Discovery, 750w 3.0T) replaced the conventional CT-procedure. A treatment plan was created on a synthetic-CT (sCT, MriPlannerTM, Spectronic Medical AB). A CT was acquired, strictly used in the background for monitoring and evaluation of the implementation process. All decisions were based on the MRI-simulation information. The potential problems and pitfalls were identified.
Results: 27 of 28 patients successfully received an MRI-only treatment. One patient was excluded due to the FOV. The PTV mean dose difference was less than the chosen tolerance (1.0%) for 24 patients. The maximum difference was 1.1% (due to difference in the set up). The marker identification (100%) based on MR and patient positioning based on the identified marker coordinates were successfully performed. Identified areas of attention included MR-scanner performance, MR acquisition protocols and the risk for â€˜human errorsâ€?. The most commonly identified issue was related to patient size, showing the importance of having a technique which allows large FOVs.
Conclusion: We have identified a set of tasks to be performed to avoid the most common potential problems in an MRI-only workflow. This makes a strong foundation for a safe delivery and for new implementations of MRI-only treatments in the future.
Funding Support, Disclosures, and Conflict of Interest: This project is funded by VINNOVA, the Swedish Innovation Agency.