ESTRO 2025 - Abstract Book

S4262

RTT - Education, training, advanced practice and role developments

ESTRO 2025

Figure 2: Workflow decision tree

Conclusion: With proper training, the RTT-only workflow is feasible and reduces RO workload. It could improve treatment efficiency in the future.

Keywords: RTT-only adaptive MRIgRT

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Proffered Paper Implementation of RTT-only driven online adaptive radiotherapy for rectal cancer based on diagnostic CT scans Daniëlle J.P.M. de la Bije, Judith H Sluijter, Claudia S.E.W. Schuurhuizen, Maarten L.P. Dirkx, Joost J.M.E. Nuyttens Radiotherapy, Erasmus MC Cancer Institute, Rotterdam, Netherlands Purpose/Objective: To improve the efficiency of radiotherapy treatment for rectal cancer, we developed an innovative online adaptive radiotherapy (OART) workflow that utilizes available diagnostic CT scans for treatment preparation, replacing the need for a conventional planning CT scan. This approach is anticipated to streamline treatment initiation, thereby reducing the waiting time until start of treatment for the patient and optimizing resource utilization. In our routine clinical practice we have implemented this technique using a workflow fully driven by radiotherapy technicians (RTTs). Practical aspects of this RTT-only implementation and its impact on treatment time are discussed. Material/Methods: OART is performed using an Ethos therapy system (Varian, a Siemens Healtineers Company, Palo Alto, USA) equipped with a high-quality cone-beam CT (HyperSight). Before starting OART for rectal cancer, the RTTs got two clinical lectures, describing details of the treatment workflow and relevant delineation guidelines. Next, they individually followed hands-on sessions on the Emulator, a test and training environment identical to the clinical system (version 1.1), under the guidance of a technical physician. After completing several test cases, two trained RTTs were allowed to perform OART clinically under the supervision of a radiation oncologist. As RTTs gained sufficient clinical experience, a transition was made to an RTT-only workflow, eliminating the need for physician's