ESTRO 2025 - Abstract Book

S4263

RTT - Education, training, advanced practice and role developments

ESTRO 2025

supervision at the treatment unit. To ensure quality and safety, a physician or technical physician reviewed the treatment reports offline. To evaluate the learning curve, treatment times per patient were analyzed by measuring the duration between the pre-treatment and post-treatment CBCT scans. Results: In September 2023, we started OART for rectal cancer with 9 trained RTTs. Within 3 months, 2 RTT-only's were certified (Figure 1). After 12 months, 17 RTTs were trained, including 12 certified as RTT-only. In February 2024, we adapted to the RTT-only workflow in clinical practice to enhance treatment efficiency and streamline patient care. The percentage of treatment fractions being delivered in RTT-only mode increased from 50% in May to 80% in October. In the first year, the treatment time for OART rectal cancer patients gradually dropped by 25% (Figure 1).

Conclusion: An RTT-only workflow for OART in rectal cancer patients, based on diagnostic CT scans, was successfully implemented. After implementation, a gradual decrease in treatment time was observed, showing the increasing efficiency and familiarity of the clinical team with the new workflow.

Keywords: RTT only, Adaptive treatment, Rectal cancer

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Digital Poster Evaluation of clinician lite, advanced adaptor led workflow in CBCT guided online adaptive radiotherapy for urological cancer Amy J Ward 1 , Dom Withers 2 , Kirsty-Anne Daly 3 , Siobhan Graham 3 , Ewan Almond 2 , Helen Killen 1 , Maria Martinou 1 1 Clinical Oncology, Barking, Havering and Redbridge University Hospitals NHS Trust, Romford, United Kingdom. 2 Radiotherapy Physics, Barking, Havering and Redbridge University Hospitals NHS Trust, Romford, United Kingdom. 3 Radiotherapy, Barking, Havering and Redbridge University Hospitals NHS Trust, Romford, United Kingdom

Purpose/Objective: In 2020 our centre was the first in the UK to go live with online adaptive radiotherapy (oART) using Varian ETHOS therapy. Clinician availability on-set for all 20 fractions of prostate or bladder oART was limiting the number of patients who were offered treatment. We developed a program to train RTTs, physics and dosimetry staff to deliver