ESTRO 2024 - Abstract Book

S5737

RTT - Education, training, advanced practice and role developments

ESTRO 2024

140

Proffered Paper

Bridging Australian RTT contouring capabilities for pelvic online adaptive RT with virtual education

Meegan Shepherd 1,2 , Alexander Podreka 1 , Brian Porter 1 , Venkatesha Venkatesha 3 , John Atyeo 1,2 , Jeremy Booth 1,4

1 Northern Sydney Cancer Centre, Radiation Oncology, St Leonards, Australia. 2 Monash University, Medical Radiaiton Science, Clayton, Australia. 3 NSW Health: Royal North Shore Hospital, District Research, St Leonards, Australia. 4 University of Sydney, nstitute of Medical Physics, School of Physics, Camperdown, Australia

Purpose/Objective:

Traditional radiotherapy treatment planning workflows allow for Radiation Therapists (RTTs) and Radiation Oncologists (ROs) to contour pelvic organs at risk (OAR) under minimal time pressure 1. At the Northern Sydney Cancer Centre (NSCC) in Australia, an Ethos online adaptive cone-beam CT (CBCT) solution was implemented in 2020. To streamline the online adaptive radiation therapy (oART) workflow, RTTs are often required to edit the artificial intelligence (AI) derived OARs or ‘influencers’, normally contoured by ROs. RTTs assuming responsibility for OAR contouring can help facilitate speedy oART treatment fractions, increased number of adaptive patients, general workflow efficiencies and up-skilling of RTTs for job satisfaction and pathway to advanced practice 2-4. We investigate if virtual (non-interactive) RO-led workshops improves RTT contouring accuracy and confidence for pelvic OARs on CT and CBCT datasets.

Material/Methods:

In this ethics approved study, eligible participants were full-time permanent or extended contract (12-months or more) RTTs employed at NSCC. Baseline contouring accuracy evaluations were undertaken on four pelvis OARs that included bladder, rectum, sigmoid and bowel bag, using male and female CT datasets, in Proknow Contour Accuracy software, with inbuilt Dice Similarity Coefficient (DSC) calculations. RTTs were also surveyed pre-education for confidence and contouring accuracy for each OARs using a 5-point likert scale. Throughout the study, RTTs contour accuracy DSC was assessed against gold standard contours derived by a minimum of two consultant ROs. RTTs then completed virtual RO-led workshops (non-interactive) for each OAR which were supplemented with written documentation on OAR boundaries, derived by consultant ROs. RTTs then completed post training contouring on new (different patient) CT and CBCT datasets. Each OAR had a ‘threshold ’DSC, 0.85 for bladder and rectum and 0.8 for sigmoid and bowel bag. Participants were allowed up to three attempts on post training datasets to reach the threshold DSC. Assessments between baseline, post training initial, final and number of attempts and likert scores were statistically evaluated based on Wilcoxon’s signed rank test for non-normal and paired t-test for normally distributed data.

Results:

Out of a possible thirty six RTTs, thirty five completed the pre training baseline contours and post training contours for bladder and rectum. Thirty two RTTs completed the post training contouring for sigmoid and bowel bag. Significant