Copenhagen, Denmark
Onsite/Online

ESTRO 2022

Session Item

Sunday
May 08
10:30 - 11:30
Auditorium 15
AI & advanced practice
Cynthia Eccles, United Kingdom;
Samaneh Shoraka, United Kingdom
2270
Proffered Papers
RTT
11:00 - 11:10
A new model of care for rapid lung SABR treatment planning: Evaluation of the advanced RTT role.
Rachael Wooder, United Kingdom
OC-0464

Abstract

A new model of care for rapid lung SABR treatment planning: Evaluation of the advanced RTT role.
Authors:

Rachael Wooder1, Neil Bayman2, Clara Chan2, Joanna Coote2, Corinne Faivre-Finn2, Rhiannon Goldstraw3, Margaret Harris2, Laura Pemberton2, Ahmed Salem2, Hamid Sheikh2, Philip Whitehurst4, David Woolf2

1The Christie NHS Foundation Trust, Christie medical physics and engineering , Manchester, United Kingdom; 2The Christie NHS Foundation Trust, Networked services, clinical oncology, Manchester, United Kingdom; 3The Christie NHS Foundation Trust, Christie medical physics and engineering, Manchester, United Kingdom; 4The Christie NHS Foundation Trust,, Christie medical physics and engineering, Manchester, United Kingdom

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Purpose or Objective

Lung SABR treatment is managed by a multidisciplinary team to ensure optimal delivery of care. The incorporation of a lung SABR advanced practitioner (specialist RTT) role to delineate target volumes and organs at risk (OAR) aims to improve service efficiency. This study evaluated inter-observer variability as well as target volume and OAR delineation acceptance. 

Material and Methods

An initial pilot study assessed if there was a statistically significant difference in OAR delineation between advanced practitioners and radiation oncologists. Following a training session and the provision of a supporting OAR atlas 2 advanced practitioners and 5 radiation oncologists delineated the heart, oesophagus, trachea, proximal bronchial tree and brachial plexus on 8 lung SABR patient CT scans. These structure sets were analysed in ADMIRE (Advanced Medical Imaging Registration Engine, Elekta AB, Stockholm, Sweden). The advanced practitioners OAR were compared against a STAPLE (Simultaneous Truth and Performance Level Estimation) volume generated from the radiation oncologist’s volumes. Inter-observer variability was measured using distance to agreement metrics.

 

PTV and OAR delineation competency was assessed separately by the completion of 10 Supervised Learning Event for Radiotherapy Planning Skills (SLERPS). All clinical lung SABR plans delineated by the advanced practitioner were then subject to peer review. After 6 months the advanced practitioner peer review acceptance rate (proportion of cases accepted without changes during peer review) was compared against that of the radiation oncologists.   

Results

The pilot study showed there was no significant difference in OAR delineation between the advanced practitioners and radiation oncologists, except for the brachial plexus (p = 0.014), highlighting this as an area for training development (Table 1).

A review of complex lung SABR plans (n=29) found the advanced practitioner peer review acceptance rate (68%) was comparable with the radiation oncologists (69%).

Over a 6 month period the advance practitioner delineated 168 patients; this was 79.6% of the SABR patient workload.

 Table 1. The median of the max distance to agreement and range for each OAR across all patients is shown. Results are compared with an independent t-test.


Median mDTA (mm) Consultant Oncologist
Median mDTA (mm) Advanced Practitioner
p
Brachial Plexus
3.6 (2.5 – 4.2)
5.0 (3.4 – 17.1)
0.014
Oesophagus
1.0 (0.8 – 1.5)
1.0 (0.8 – 1.4) 
0.82
Heart
1.3 (1 – 1.5)
1.5 (0.8 – 2.4)
0.49
PBT
1.2 (0.6 – 1.7)
1.3 (0.9 – 1.7) 
0.8
Trachea
1.2 (0.8 – 1.6)
1.2 (0.6 – 1.8) 

0.78

Conclusion

With appropriate training the advanced practitioner is competent delineating OAR and planning target volumes for lung SABR. The lung SABR advanced practitioner role has successfully reduced clinician workload.