Introduction The significantly greater cost of proton therapy compared with X‐ray therapy is frequently justified by the expected reduction in normal tissue toxicity. This is often true for indications such as paediatric and skull base cancers. However, the benefit is less clear for other more common indications such as breast cancer, and it is possible that the degree of benefit may vary widely between these patients. The aim of this work was to demonstrate a method of individualised selection of left‐sided breast cancer patients for proton therapy based on cost‐effectiveness of treatment. Methods 16 left‐sided breast cancer patients had a treatment plan generated for the delivery of intensity‐modulated proton therapy (IMPT) and of intensity‐modulated photon therapy (IMRT) with the deep inspiration breath‐hold (DIBH) technique. The resulting dosimetric data was used to predict probabilities of tumour control and toxicities for each patient. These probabilities were used in a Markov model to predict costs and the number of quality‐adjusted life years expected as a result of each of the two treatments. Results IMPT was not cost‐effective for the majority of patients but was cost‐effective where there was a greater risk reduction of second malignancies with IMPT. Conclusion The Markov model predicted that IMPT with DIBH was only cost‐effective for selected left‐sided breast cancer patients where IMRT resulted in a significantly greater dose to normal tissue. The presented model may serve as a means of evaluating the cost‐effectiveness of IMPT on an individual patient basis.

Introduction: Australia's first proton beam therapy (PBT) service, The Australian Bragg Centre for Proton Therapy and Research, is scheduled to open in the near future providing PBT for patients closer to home. Patients currently access Commonwealth funding for PBT via the Medicare Medical Treatment Overseas Program (MTOP). Proton versus photon treatment planning is a prerequisite for the MTOP application. The Royal Adelaide Hospital (RAH) Department of Radiation Oncology has been providing this since 2016. We aim to provide a descriptive overview of our proton versus photon treatment planning process, presenting a summary of the comparative planning results and the treatment pathways selected for the patients referred. Methods: All patients referred to the RAH for comparative planning between January 2016 and December 2018 were included in the analysis. Comparative plans were generated for each case using Pinnacle or Eclipse treatment planning systems. The planning techniques used and plan quality metrics were reported. Results: Forty three patients were referred for comparative planning. The age range was 1-63 years, with the majority (72%) being paediatric patients (age ≤18 years). Of the 19 cases that have been submitted to MTOP, 16 have been accepted and 3 denied. Two of the accepted cases chose not to travel abroad for PBT. The other 14 cases have received PBT overseas. Conclusions: The RAH has provided an important service to demonstrate the dosimetric difference between PBT and photon therapy for Australian patients, an important step in supporting the funding of patients for treatment overseas.

To improve the patient experience by providing ways of relaxing the patient, making them more comfortable for treatment, and also creating a more reproducible position for geometric accuracy a service evaluation was completed. A service evaluation was undertaken to ascertain how to increase patient comfort and their ability to relax, thus enhancing their experience, whilst creating a more reproducible position to improve geometric accuracy. Method and Materials: Sample size of 40 randomised patients All undergoing pelvic radiotherapy All selected patients treated with and without the grip ring for a comparison Each patient completed a survey relating to comfort/relaxation Data from survey was sourced and divided into positive and negative responses Data from daily CBCT images acquired from 10 patients in both set ups (10 with grip ring, 10 without grip ring) Results: Data from 40 separate surveys revealed 77% of patients felt more comfortable and relaxed while holding the grip ring, 6% disliked the grip ring and 17% felt no change. Only 20% of patients had errors outside the tolerance band whilst holding the ring compared to 40% of those who did not. This was based on images with directional errors of >0.3cm being out of tolerance. Conclusion and Discussion: A high percentage of patients found the grip ring made treatment more comfortable and relaxed. These results are indicating that the grip ring leads to an improvement in patient position which leads to a more accurate setup. Introducing a more comfortable method of immobilisation that helps to relax the patient could also be used as a tool to help relax dementia patients. The findings from this service evaluation shows the grip ring to be a low cost piece of immobilisation that enhances the patient experience and comfort whilst also improving immobilisation and geometric accuracy.