Holyoake, DL, Robinson, M, Grose, D et al. (7 more authors) (2016) Conformity analysis to demonstrate reproducibility of target volumes for Margin-Intense Stereotactic Radiotherapy for borderline-resectable pancreatic cancer. Radiotherapy and Oncology, 121 (1). pp. 86-91. ISSN 0167-8140
Abstract
Margin-directed neoadjuvant radiotherapy for borderline-resectable pancreatic cancer (BRPC) aims to facilitate clear surgical margins. A systematic method was developed for definition of a boost target volume prior to a formal phase-I study.Reference structures were defined by two oncologists and one radiologist, target structures were submitted by eight oncologist investigators and compared using conformity indices. Resultant risk of duodenal bleed (NTCP) was modelled.For GTV, reference volume was 2.1cm(3) and investigator mean was 6.03cm(3) (95% CI 3.92-8.13cm(3)), for boost volume 1.1cm(3) and 1.25cm(3) (1.02-1.48cm(3)). Mean Dice conformity coefficient for GTV was 0.47 (0.38-0.56), and for boost volume was significantly higher at 0.61 (0.52-0.70, p=0.01). Discordance index (DI) for GTV was 0.65 (0.56-0.75) and for boost volume was significantly lower at 0.39 (0.28-0.49, p=0.001). NTCP using reference contours was 2.95%, with mean for investigator contour plans 3.93% (3.63-4.22%). Correlations were seen between NTCP and GTV volume (p=0.02) and NTCP and DI (correlation coefficient 0.83 (0.29-0.97), p=0.01).Better conformity with reference was shown for boost volume compared with GTV. Investigator GTV volumes were larger than reference, had higher DI scores and modelled toxicity risk. A consistent method of target structure definition for margin-directed pancreatic radiotherapy is demonstrated.
Metadata
Item Type: | Article |
---|---|
Authors/Creators: |
|
Copyright, Publisher and Additional Information: | © 2016, The Authors. Published by Elsevier Ireland Ltd. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/) |
Keywords: | Pancreatic cancer; Borderline-resectable; SBRT; Target volume definition; Radiation therapy quality assurance |
Dates: |
|
Institution: | The University of Leeds |
Academic Units: | The University of Leeds > Faculty of Medicine and Health (Leeds) > School of Medicine (Leeds) > Leeds Institute of Cancer and Pathology (LICAP) |
Depositing User: | Symplectic Publications |
Date Deposited: | 19 Aug 2016 11:04 |
Last Modified: | 15 Jan 2018 17:27 |
Published Version: | https://doi.org/10.1016/j.radonc.2016.08.001 |
Status: | Published |
Publisher: | Elsevier |
Identification Number: | 10.1016/j.radonc.2016.08.001 |
Related URLs: | |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:103877 |