TY  - JOUR
A1  - Kersemans, Veerle
A1  - Beech, John S.
A1  - Gilchrist, Stuart
A1  - Kinchesh, Paul
A1  - Allen, Philip D.
A1  - Thompson, James
A1  - Gomes, Ana L.
A1  - D’Costa, Zenobia
A1  - Bird, Luke
A1  - Tullis, Iain D. C.
A1  - Newman, Robert G.
A1  - Corroyer-Dulmont, Aurélien
A1  - Falzone, Nadia
A1  - Azad, Abul
A1  - Vallis, Katherine
A1  - Sansom, Owen J.
A1  - Muschel, Ruth J.
A1  - Vojnovic, Borivoj
A1  - Hill, Mark A.
A1  - Fokas, Emmanouil
A1  - Smart, Sean C.
T1  - An efficient and robust MRI-guided radiotherapy planning approach for targeting abdominal organs and tumours in the mouse
T2  - PLoS one
N2  - Introduction: Preclinical CT-guided radiotherapy platforms are increasingly used but the CT images are characterized by poor soft tissue contrast. The aim of this study was to develop a robust and accurate method of MRI-guided radiotherapy (MR-IGRT) delivery to abdominal targets in the mouse.
Methods: A multimodality cradle was developed for providing subject immobilisation and its performance was evaluated. Whilst CT was still used for dose calculations, target identification was based on MRI. Each step of the radiotherapy planning procedure was validated initially in vitro using BANG gel dosimeters. Subsequently, MR-IGRT of normal adrenal glands with a size-matched collimated beam was performed. Additionally, the SK-N-SH neuroblastoma xenograft model and the transgenic KPC model of pancreatic ductal adenocarcinoma were used to demonstrate the applicability of our methods for the accurate delivery of radiation to CT-invisible abdominal tumours.
Results: The BANG gel phantoms demonstrated a targeting efficiency error of 0.56 ± 0.18 mm. The in vivo stability tests of body motion during MR-IGRT and the associated cradle transfer showed that the residual body movements are within this MR-IGRT targeting error. Accurate MR-IGRT of the normal adrenal glands with a size-matched collimated beam was confirmed by γH2AX staining. Regression in tumour volume was observed almost immediately post MR-IGRT in the neuroblastoma model, further demonstrating accuracy of x-ray delivery. Finally, MR-IGRT in the KPC model facilitated precise contouring and comparison of different treatment plans and radiotherapy dose distributions not only to the intra-abdominal tumour but also to the organs at risk.
Conclusion: This is, to our knowledge, the first study to demonstrate preclinical MR-IGRT in intra-abdominal organs. The proposed MR-IGRT method presents a state-of-the-art solution to enabling robust, accurate and efficient targeting of extracranial organs in the mouse and can operate with a sufficiently high throughput to allow fractionated treatments to be given.
Y1  - 2017
UR  - http://publikationen.ub.uni-frankfurt.de/frontdoor/index/index/docId/44046
UR  - https://nbn-resolving.org/urn:nbn:de:hebis:30:3-440469
SN  - 1932-6203
N1  - Copyright: © 2017 Kersemans et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
VL  - 12
IS  - (4): e0176693
SP  - 1
EP  - 21
PB  - PLoS
CY  - Lawrence, Kan.
ER  -